For the pad issue, you may want to consider Adam's 15mm cordless swirl killer, and the two-step kit (includes compound and finishing polish, plus brush for pad cleaning every panel or half panel (hood, roof, etc, clay bar, and recharging station). I think it will serve your needs just right, vs the Ryobi and it's size/pad limitation. The backing plate determines what size pads you can use, and the Ryobi unit may just get in the way if it even allows you to use the 5-6" backing plate.