It cant hurt to change diff oils early,I have for years used castrol 80w90 hypoid and never had any bearing/diff problems. One pint will do ft and rears with some left over.The only oil i stick with from honda is gn4 for the engine.Honda at 10 hours will change oil,adjust brakes and cables,adjust the valves.I personally would save ALOT of money and do it yourself,specially when the new hondas have disc brakes.The valves dont need to be adjusted untill they start to make tapping noise all the time(hot and cold).I havent had to adjust mine yet(218 Hrs)....