I have the Eggbeater SL's, Eggbeater Ti's, and Quattro SL's, and I used to have the Candy C's. The only pair I've disassembled is the Eggbeater SL's, and they had sealed bearings.

For that matter, I thought they were all sealed bearing's.

I haven't had any trouble with any of them. Although I'm not really pleased with the Quattro's, but not because of quality issues.