........and then I'll just quietly slink away.......AND BUY SOME MONSTROUS MOTHER****ERS!

Sorry, I mean purchase some replica RS-6 17 x 7.5s.

Thanks to youse guys, I now 'get it' as far as:

205 x 45 x 16 =

205 x 40 x 17 =

205 x 35 x 18

to keep the same rolling radius etc.

however........

based on the fact that I'm going for 17s, I want to know the limit for tyre width:

ie. would 225s catch/rub anywhere on 7.5 rims?

I was thinking the extra little 'bulging' would act as a bit more rim protection against potholes/curbing?.......or would they look stupid, or just not fit?

Oh, and by the way, I've seen threads mentioning the quality of aftermarket alloys with respect to buckling/vibration @ speed etc. Anyone got opinions on the 'Wheelbase' VAG replicas compared with the original 'Spider 16s' regarding strength/quality of finish?.

Thanx for your patience (and repeating most of the stuff you told Eatsoot and the rest)

Verr.

215 would be the best width (215/35/17), but go and actually have a look at some tyres - some have a more rounded profile than others and some actually have a rubber lip to protect the rims. It would be worth paying a bit more for a tyre that had a bit of rim protection as that would actually save you money in the long term.

I asked to have 215/40 R17 put on my alloys. They give more grip in the dry, look a bit better, the higher profile does protect the rim and should give better ride quality.

I went over a crater/pothole at 50mph - massive bang, I **** myself. I really didnt want to look at the wheel when I got out, but it was fine! Couldnt believe it. Well worth the extra money for the wider and therefore taller tyre