My old 667MHz PowerBook G4 Titanium Onyx is still using the same battery it came with when I bought it 2001. It is a 4200 mAh battery and iStat reports that it has 432 cycles. Yet, it still lasts just as long as when I bought the battery which is around 3 hours and iStat reports 100% health efficiency. Is this normal for these batteries or am I just lucky?