I would try the rev 682 and see if you have better luck. I only have about 100 games and my simanimal just goes to a black screen and red steel doesnt load. I know on read steel i have to create alternate .dol file on the usb. You might chek on there google code site and see if other people are haveing similiar problems with the rev 700.
I noticed in this thread they say all 200 or so games work with rev 700. If his information is correct i would say rev 700 is working pretty good.
I was having the same problem, some games worked, some only for a few min or an hour. I bought a new HDD Case off ebay for $10 and i haven't had a problem since.