It's probably ok. My PSU blows on my graphics cards.
No, it doesn't. The PSU fans all exhaust air from
I do not think that it will make much difference. I have Antec 900 cases with bottom mounted power supplies. I orient the PSU's with the fan up. The combination of the lower front fan and the PSU does a great job cooling my hard drives. Exhaust air from the PSU is never more than 3 or 4 C (as measured with an electronic cooking thermometer) above ambient temps.