Summary: We own a couple Buffalo rackmount Terastations. We primarily use these for storing documents and data. We have them setup to mirror each other. We have not had any problems with them thus far and one of them we have owned one of them for a couple of years now. I would not expect this to be extremely speedy device and I don't know if I would store database files, or anything else needed for real time applications.
Summary: I bought this TeraStation to use as a network backup device for my domain controller / file server at home (yeah, I'm a geek - I maintain SOHO level stuff at home to keep my sysadmin skills from getting dusty). At any rate, I've got 5 TB of storage on the server and I use the Buffalo as a backup.
Summary: Otherwise a good product. Minus an egg for the AD Users issue. Also run a 2 TB Buffalo NAS at home in RAID 1. Stream from it to my PC then to my XBOX via media center connector. HD movies look great. Nice alternative storage for your HTPC.
Pros: Low Price, repectable data speeds, fits 4 post rack
Cons: Buffalo Support is terrible. Beware, if implementing into a large Active Directory, will not pull users. It pulled my groups fine but not users. Called Buffalo twice and even after firmware update to 1.50 still won't pull domain users. I have 2000 user accounts and Buffalo claims it can handle up to 10,000... not true. tHer is a work around by joining it to a work group and having it learn credentials buy browsing to a special share.
Summary: Once you get this unit set up and configured properly it seems to be stable and reliable. The documentation is pretty limited. For example, we built this out in a test environment using a slightly different network configuration than it was deployed into. During unpacking for the final deploy, the tiny little Manual/Auto switch on the back was bumped to Auto.
Summary: Disk space is getting very cheap and 1TB USB drives are becoming common. However, as drives get bigger, and we store more data, there's more to get lost if a drive fails. Backing up to CD/DVD is becoming less attractive as they get left behind in this "space race"; Blu-Ray is looking attractive but still relatively expensive. The TeraStation made a lot of sense to me as my primary back-up.
Summary: A bit pricey, maybe, but it does the job of high volume storage superbly with plenty of space for back-up using the RAID options. The unit operates quietly and is quite small, given the amount of storage it can accommodate. It also works reasonably quickly, although the speed of wireless networks in particular is likely to be limited by the capability of the wireless hub, switch or laptop / PC Etc.