now theres a question..........
wheels are completely down to personal choice, obviously the guy or girl who put the lupo wheels on thought they looked good, so your best bet is to look around and se what takes your fancy, and more to the point what you can afford!!
easy options are the standard vw wheels from mk2 golfs or corrado's and the like which i think do look good if done right
as for size i'm not exactly sure but 16's will fit but i would stick to 14's or 15's with 195 tyres on them, this is only a personal preferance and i'm sure someone knows more about sizes and stuff
good luck with the search
