2002M3Drew

I am thinking about buying a set of 911 rims in the 951 offset for my 83 911. I know that the main offset difference is in the 8", where it is a larger offset than the 911 8". I also know that both alloys allow more backspace for the calipers.

Is there any advantage (with my stock brakes) of running these 7's and 8's over the standard 911 offsets? I'm concerned about having a narrower track on the rear axle. Anybody running these?