Deako, if you go for the TD's, for 215 tires, I think 7.5 is the best choice.
I had the same problem as you are having now. Nobody tried 17 inch TD's on nqsbbk. So, to be sure not to make a mistake again (I previously bought some OEM wheels that did not clear the brakes) I went for ET45 and 8inch wide rims.
The clearance is huge in my case.
If you tell me the bell size (the distance from the disc surface to the rim hub) I can give you some indication on whether the TD will clear the brakes.
As far as I know the bell size (not sure this is the correct expression) is 25mm for mk5 platform and 15mm for the mk4 platform but I need some confirmation.