the ballence is REALLY important. ive had people say ballence doesnt matter becuase they only use 5 - 30 gram pieces to fix it, and 5 - 30 grams wont make much difference right?... due to centripital force, 10 grams spinning at about 60 ks an hour ends up weighing about 3000 times heavier. now do you think you would notice 30 kilos of weight spinning off centre? I'm sure my maths is WAAAAAAY off but it still makes a massive difference once something starts spinning fast enough.