RAID is not the determining factor in HD life. Heat, activity, user habits and just plain luck will have a greater affect. As I understand it, RAID works best when all drives are as identical is possible. You may also read that it's better to use drives designed for RAID use rather than those for basic desktop use. I'd say read about the differences. One that I've heard suggests that drives which periodically "recalibrate" are to be avoided. This means that if a drive within a pair takes a rest break to realign the pair may break. I gave up on RAID long ago. It may have its purposes in the enterprise arena but I doubt the regular user gets more benefit than they do headaches from employing RAID. If you really need it, do it. If it's just to impress yourself or be cool, I think there are better ways to accomplish that.
1. Are there any issues with mixing brands in RAID10?
2. Any HDD driver conflicts to worry about?
3. Only if you have a RAID10, what's the average life of one of your drives?
4. Is BIOS the best stable way to setup and maintain RAIDs? Right now my RAID0 is setup in BIOS.
5. Any way to throw in a SSD as cache for the HDD in RAID10, or should I just go with one of these WD2500BHTZ as a SSD will undoubtedly live a short life.
Currently RAID0 has two WD10EZEX, will be adding three SeaGate with same specs for the RAID10, and two more WD later on. They'll all be 1TB, 7200RPM, & 64MB cache.
Thanks to the genius out there who can help me.

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