thanks a lot ... so i have some more open items on my check-list
for most of us the motor pinions seem to be the most critical parts (replace after 150 - 300 flights), followed by the tailrotor-bearrings, dampers and belt (although esp the dampers seemed to me undestructible... )
furthermore i found the endurance of the servos (i tested hs65hb, savoxsh0254, align ds410) very similar by 400 flights on average, the old motor adapter by 500 flights (the special shaft will keep much longer...) - and now the bladegrip-bearrings by 1000 flights... but it should be replaced a little bit before, i guess
macem