2) Heat -You're building HOME PCs in RACKMOUNT Cases - you're not buying SERVER level hardware. So all this crap about "death by heat" is a bit over the edge. Yes, it gets hot - No, its not doing to kill you. You wont' be buying HP Proliant servers after all...
I'm not going to say it will kill anyone, but correct me if I am wrong: Typical servers in a datacenter are not under heavy load most of the time (hence the race for virtualization now), and don't have piping hot video cards in them either. Under load, I stand by my statement that this is going to run hot, and will need airflow to move the heat behind the case. My multiboxing PC is in a rack mount chassis, and I usually have a separate fan running, and I generally need to keep the top off it as well. Then again, I'm putting 5 instances on one PC, not 1 instance per 5 PC. It wont be AS bad with 1 per PC but it's still going to be a lot of heat.