43823 25GB 4x M-Disc BD-R - 5 Pack Jewel Case

I bought these to backup the data I cannot afford to lose in a virus, malware or ransomware attack. Bought from Amazon EU, and each disc is shrink wrapped and all barcodes match Verbatim's website. I saw concerns about scratches in the inner ring and burn failures so I was concerned given the price. While the scratches are definitely there, they're in the inner ring where the 3 serial numbers (1 per layer) are, so nothing is written there and they don't impact quality. The discs are identified as MID: VERBAT-IMk-000, which verifies on the BluRay site as HTL (High-to-low Inorganic) BDR V3.0. Burned with a Pioneer BDR-XD05T drive from Aug 2014 (which has no claim to support MDisc on it, but works because MDisc adheres to all BluRay standards). Used ImgBurn (from a mirror site to avoid the Adware from the genuine site) and created a 100GB ISO Image (Mode1/2048 using ISO9660+Joliet+UDF with UDF 1.50). My first disc image contained 25,180 files in 595 folders totalling 92,368,211,531 bytes. I also MD5 summed each file and saved the checksums to the BD as well. It took 26 minutes to create the image on the local disc, then I burned at 2x speed for safety which took 2 hours 55 minutes, then 1hr 31 minutes to verify the disc to the ISO. I also verified all MD5sums after the disc had cooled off which tool another 2 hours 32 minutes. Both the ImgBurn and the MD5Sum file verifications were good. The discs show up as 90.2GB in Windows, but that is because of the difference in units i.e. GB vs GiB. In short, I am happy that these Discs are as described and when burned at 2x speed, have no failures. I would say ignore the "you don't get 100GB", the "scratches on the inner ring" and "burn failure" reviews on here. My opinion is that those reviews come from misunderstandings about the tech and probably burning directly without using ISO first. I will be buying more of these again. As to whether they last longer than standard BD-XL or whether I should be using single layer 25GB MDiscs, only time will tell. I'll probably check the MD5 sums once evert couple of years to ensure the backups are still valid and take more/move files to a new disc if there are issues.

You can fit 45min+ of FM RF captures of VHS (16msps 8-bit FLAC) or a full MiniDV tape on a single 25GB disc, its only a shame 128GB discs are only made by Sony but never got the M-Disc adaption. All modern BD worm disc media is long life reliable (HLT discs) but M-Disc's molding is what makes it really stand out, though some will argue glossy carbon is a more reliable substraight, your paying for the better grade plastics and better grade meterial. ISO/IEC 10995:2011 & ECMA-379 - are the standards it confroms to if you want a fun read. At the end of the day, we all will most likely be long dead before these discs degrade, unless they are in a house fire not much can break the encasing polycarb plastics, these are perfect to backup your factory stamped DVD/BD discs and or anything else for long term archival at room tempratures.

These are expensive to buy, but if you want an offline copy of important data (financial record, children pictures/videos etc etc), this is pretty much the only consumer level device to do this. Optical media has also had a good history of backward compatibility spanning many decades. The claimed life of many hundreds of years is, of course, going to be hard to prove, but nothing else claims this longevity. The Blu-Ray's can be written with any Blu-Ray writer, but I have always used one with MDISC branding (which is technically only needed for MDISC DVDs). The key thing is they can be read by ANY drive and written with standard software.

all ok

Works nicely with my internal Pioneer BDR-213EBK and Brun Aware software on Windows 11. It takes my PC about 3 hours to right a disk full and the same again to verify. I have written to 10 disks so far with out a single failure and it is nice knowing I have the surety of not losing precious digital pictures, music and hobby info

Worked great in my Asus blu-ray disk writer. They are in a standard CD case with a printable and writeable disk label. I used Sharpie permanent marker to write on mine. They are reported to have a 1000 year life but someone else will have to report back in that feature!

Poor Quality discs out of a batch of 10 I have had 3 fails so far considering the price of these discs they should be better quality than this not happy at all with this failure rate! turning out to be total rubbish discs charging an arm and a leg for complete rubbish!

These seem to work fine, though I've only one blu-ray drive to test them with, so I only know that they'll read without problems in the same drive that wrote to them... Sha256 sums on files before packing in to an iso and then after reading from the burned disc are identical. And burning from Linux is pretty easy using k3b (create a <25GB iso image file of your files first, then burn that iso using the growisofs option, set k3b NOT to auto-eject discs upon completion and to show advanced GUI settings) and a Hitachi-LG burner drive. But I'm not 100% sure if these are really truly M-discs. They are branded as M-discs, but with the exception of the branding printed on the top side they are visually identical to standard 25GB BD-R blu-ray discs from Verbatim. Same colour, same "barcode" near the inner edge... K3b also reports identical media information for these as it does for standard BD-R discs, and although in practice k3b tends to burn all discs at about 1x speed, it detects these discs as being capable for 2x, 4x and 6x burning, just like normal BD-R discs, even though in theory M-discs have a max speed of 4x. There were some reports in 2022 that verbatim had changed production of their 25GB M-diss to be more similar to their standard blu-ray discs, maybe blu-ray and M-disc are the same now and verbatim does a "binning" operation where most discs from one production line get sold as blu-ray, whereas those which pass a large battery of quality tests get labelled as M-disc before leaving the factory. True M-discs, the 4.7GB sort aren't made anywhere, at all, any more as far as I can tell, and 4.7GB is inconveniently small, 25GB discs for backing up the most important data makes sense, 4.7GB discs force one to start doing inconvenient splitting of big 7z files so they can be placed across multiple discs. These 25Gb blu-ray M-discs are supposed to have reasonably similar lifespans, but I can't be sure whether they're really any different than verbatim's standard BD-R (metal ablative type) blu-ray discs. There's a lot of speculation online both ways, and it is hard to be sure of the situation. To be quite clear, these discs work absolutely fine, on that regard I can give 5 stars, but I don't know whether they'll actually be more durable than the standard BD-R discs, hence the lowered rating given my fears they might just be regular blu-ray's selected by post-production quality testing. If anyone can enlighten me I would really like to know about that. Thanks

Mettent un temps fou poyr être gravés quand ça marche...

Helt OK!

Cosa sono i dischi M-Disc? Il design di M-DISC ha lo scopo di fornire una maggiore longevità dei media d'archivio . Millenniata (la ditta che detiene il brevetto) afferma che le registrazioni DVD M-DISC correttamente archiviate dureranno 1000 anni. Il DVD M-DISC si presenta come un disco standard, tranne per il fatto che è leggermente più spesso e quasi trasparente. Mentre le proprietà esatte di M-DISC sono un segreto commerciale , i brevetti che proteggono la tecnologia M-DISC affermano che lo strato di dati è un " carbonio vetroso " e che il materiale è sostanzialmente inerte all'ossidazione e ha un punto di fusione di 200–1.000 ° C (392–1.832 ° F). Secondo Millenniata (la ditta che l'ha inventati), la US Naval Air Warfare Center Weapons Division del Dipartimento della Difesa degli Stati Uniti ha scoperto che i DVD M-DISC sono molto più durevoli dei DVD convenzionali. "I dischi sono stati soggetti alle seguenti condizioni di prova nella camera ambientale: 85 °C (185 °F), 85% di umidità relativa (condizioni specificate in ECMA-379) e luce a spettro completo ". Secondo un test di invecchiamento accelerato del Laboratorio nazionale francese di metrologia e prove a 90 °C (194 °F) e 85% di umidità, i DVD+R con uno strato di registrazione inorganico come gli M-DISC erano ancora leggibili dopo 250 ore, tuttavia con un tasso di errore superiore alla soglia e sono stati valutati "meno di 250 ore" equivalente alle offerte concorrenti. Le prestazioni sono state migliori di diverse marche di DVD che utilizzano coloranti organici, dove i dischi non erano sempre leggibili dopo 250 ore; leggermente inferiore rispetto a un altro marchio che ha ottenuto un errore di lettura inferiore ed è stato valutato "250 ore"; molto meno della tecnologia DVD in vetro ( Syylex ) che è stata valutata "più di 1000 ore". Millenniata, Inc. è ufficialmente fallita nel dicembre 2016. Asus , LG Electronics , Lite-On , Pioneer e Verbatim producono unità in grado di registrare supporti M-DISC. Ritek produce supporti Blu-ray M-DISC, venduti con i marchi Ritek e M-DISC. Verbatim produce dischi in co-branding, commercializzati come "Verbatim M-DISC". Io ne ho bruciato uno con masterizzatore Verbatim modello 43888 (quello 4K Ultra HD per intenderci) e il disco è venuto perfetto. Leggibile da altri lettori Blu-ray anche più vecchi. Ora solo il tempo dirà quanto dura. A 5€ a disco vergine credo che ne valga la pena. Panasonic e Sony hanno i loro archive optcial ma primo dichiarano 50 anni il primo e 100 anni il secondo, secondo i prezzi sono molto più alti soprattutto nel caso di Sony (basti vedere quanto costano le cartucce Optical Disc Archive di Sony e quanto le loro unità Optical Disc Archive. Certo possono immagazzinare più dati fino a 5,5 TB per cartuccia ma a che prezzo? Quindi per noi mortali un semplice masterizzatore M-Disc e questi dischi da 25 GB o da 100 GB sono più che ottimi per archiviare definitivamente i nostri ricordi/dati.

I started using my recorded and these discs today. So far, I burned two out of five and I've experienced no errors. Take in count that write speed is 4x. I believe there are other discs, more expensive, that are to be written at 6x. At 4x it writes at 18 MB/sec (like a typical USB pen drive for me) and it takes nearly two hours to burn a 90 GB blu-ray, plus an additional hour and half to verify the data written. Worth mentioning that I was able to burn 90 GB only. Nero didn't allow me to write more than 90 GB.

Tylko 1 z 5 płyt 100gb udało się zapisać. Pozostałe ulegały uszkodzeniu w trakcie zapisu. Nie miałem tego problemu z płytami 25gb. Nie polecam. Szkoda pieniędzy.