hi folks, i've got a 2000 (W-Reg) 1.8T Quattro Sport and need to replace all 4 of the tyres as they are pretty low. It has the standard 17" multispoke wheels on it at the moment fitted with Kumho 225/40/17 tyres. this size seems quite uncommon and i'm having trouble tracking down a decent tyre at a decent price. is 225/40 definitely the correct size for this car? i can't find anything in the owners manual that tells me. would ideally like some Goodyear Eagle F1's as i had these on my last car and they were superb. also - the concert tape head unit/changer combo is terrible and one of the standard speakers sounds blown. has anyone done a successful upgrade to aftermarket head unit and speakers? I've heard horror stories about constant buzzing due to interference with the airbag??! any tips? hope someone can help!