Personal preference is 15's, but I also run my car a little lower than standard.
There will not be a massive difference between these two, so if you are just driving it on the streets at stock height just go for what size you like the look of most.
When it comes to the rubbing you should...
Looking for seat rails that will allow me to mount the oem Recaros in my EK4.
Both sides would be optimal, but will also consider just the Left side if you are chucking out your passenger seat.
Located in Sweden so must be okay to ship inside EU.
Alternatively I am open to tips...