Well first impressions - It looks great
I don't know much about dollars, but 500GB is sure alot.
Make sure though, like with any hard drive, you keep a backup...somehow...
USB 2.0 is actually faster than Firewire in this case it seems... by 80mbits
5° C to 35° C
Thats alright. Hard drives start corrupting themselves past 55 degrees C. As long as its in alright conditions, you won't have a problem what so ever.