I purchased an OCZ Enyo external SSD that uses MLC flash technology. OCZ claims a Mean Time Between Failure (MTBF) of 1.5 million hours. I don't know how they analyzed the failure rates and arrived at that MTBF but it is 171 years of operation and certainly indicates that reliability is not a problem.
Tony
It can all boil down to how OCZ feels the end-user will use the product. But a 1.5 million hours MBTF and a 3 year warranty should indicate OCZ has a marketing department and probably not a legal department.
SLC will start to fail after 100,000 writes where MLC will start to fail after 10,000 writes. It's not as bad as it sounds as it's typically a write to the smallest writable block that will fail. Without googling the flash chip they use internally, if you assumed that a writable block was small (say 4KB), then for a 64GB that could hold 2000 uncompressed lossless files (12k blocks per 50MB wave file) that works out to twenty million transfers for the best case before a user would see a failure.
That sounds pretty good, but the nature of HDDs and file systems indicates that you will most likely start to see failures much early than that. Mostly due to the fact that that the filesystem keeps a tables that tracks the files on the drive, these tables will be updated on every write and that organization will mostly determine how long the drive will operate before the first failure. So every file copied, tag update, album artwork update, etc will decrease the life of the drive.
Also, if you notice most SSD manufactures tell you to not defrag SSDs for two reasons: 1) its not needed 2) reduces the life of the drive. But keep in mind like HDD, SSDs will also use error correction techniques to extend the life even further (just like HDD) and just reviewing a few of the OCZ drives, appears they enable 512/24 byte ECC technique with their controllers providing more longevity with the drives.
It's hard to put an actual, real-life number on how long a MLC drive will last and as long as you keep adequate backups, you can save some cash on the SSD and buy a more expensive USB cable. But if I was going to spend your dollars for you, the SLC drive IMO would actually provide a benefit over an expensive USB cable as any data failure there would be audio gaps in the music.
To me a key point of the BDP-1 is to avoid the short comings of isochronous USB audio and you are able to drive your DAC using the AES connector. You are essentially migrating to a worse case jitter of 1 miliseconds to tens of picoseconds.
Werd, if your USB drive isn't self powered (i.e. wall wart) and if your USB cables are of different length, then perhaps you are hearing noise from the power supply. Leakage loss could be used to explain that. Probably an easy test is to determine this is to use a UPS on all your gear. That is a bit extreme though. If the drive is bus-powered then perhaps it's placement of the drive?