17" wheels front and rear what tyre profile would be best

[PYNEY]

hi all
Qbee has helped me with this question but i'm getting different answers from various tyre suppliers
very close now to buying a new set of wheels which will be 17" front and rear
so my question is I will be going for 215/40/17 front but what would be best for the rears 235/40 or 235/45

[PYNEY]

Thanks guys , I have been told that a 45 profile on the fronts may rub with a 17" wheel ?
hence why im starting with a 40 on the front , I take it you have had no such problems ? the fronts on my setup are 7.5j