My riocar, 60 gig with 2 fujitsus has similar problems. Mine seem to happen every 3 to 4 weeks though, and dont seem to be temperature related. Maybe my drives are failing .
After I applied the builder image the drives were being detected but i would still get the kernel panic 3:05 error, after I gave up and reinstalled everything it started to work. Just reloaded all my music and wating to hear from support to see what to do.