Mine runs a bit warm imo, but Im sure its fine. Its kind of in a tight spot with the same amount of space as my PS3 which is almost 4 inches of space on each side, behind it and above it. The video titled PS4 Red Light Of Death w the 360 under it looks similar to how I have mine set up, except I dont have holes on the sides and back. It ran for 12 hours yesterday and stayed the same heat wise. I could give it about 7 more inches of space above the unit, but then I wouldnt have a place for my PS3, and I dont think it would really make a difference anyways. Its been on for 30 min now and is almost as hot as it was last night before I turned it off. It runs hotter than my Slim 320GB PS3, and about the same as my Verizon HD DVR box which has plenty of air flow. I think its fine. Its not alarmingly hot or anything...