Hm.. Well never had any serious problems with my A500 and A4000 (till she died that is). Most problems came from stupid software hacks and unstable programs or overheating problems (2 HD's, CyberstormPPC/Cybervision and a KCS PC emulator (Also PowerPC';-), used to have a Cybervision3D in it as well).. When using the standard OS install + CyberGFX and PPC software with no shareware kinda hacks everything worked fine.
Then again, I hardly ever kept my Amiga's powered on when I wasn't home or was sleeping unlike my XP machine which is kept on almost 24/7.
