e30 wheels 15 or 16 and front and rear different wide?

[markus_74]

I decide to go replica may be bbs.

But I still confuse which is better for handling and speed but still comfort? 15 or 16?

15x205x55?
16x205x50?

and some offer me different wide between front 7J and rear 8J does is it good for handling? or better use all same wheel at 7J?

Thank you
Markus