Hello, I have an early 2008 mac pro with a highpoint RR4321 card in RAID 5 running snow leopard with no problems (after the initial somewhat convoluted install.) Turns out there doesn't appear to be a driver for the card for Lion. I was surprised by this, as Highpoint touted built-in OS support when Snow Leopard came out. So now I'm trying to figure out what my options are. For now, I'm sticking with Snow Leopard (and get to keep spaces). I will say that I've been pleased with the performance of the Highpoint card, and once installed, it has been very easy to maintain. The web support has been adequate (someone has always come up with the information I needed), but the software/driver support seems a step behind. I'm wondering if it's the same story with the Areca cards (on which this is based), or other comparable cards. At this point, I'd much rather have the new driver for the still very serviceable 4321 than look for a new card with better software support.