I used to run 7x15's all round on mine and I got far less scrubbage depending on which brand of tyre I was using. Got loads of scrubbage on a square shouldered Khumo, swapped to a rounded shoulder Toyo and only had a tiny bit of scrubbage (big bump and compression at high speed) with 3+ in the car. I was running nice friendly offsets though and was only lowered around 40mm but you dont need to go much lower than that with 15's.