I ordered the starter kit from SMP and I got the 4.825" backing plate with 8" pads. The 7336SP I have came with a 6" backing plate, I read that if you dont have the right counterweight on the PC that it will vibrate excessively. I loaded up the PC with the backing plate and an 8" polishing pad and it didnt seem to vibrate out of control but since I dont have anything to compare it to I figured Id ask just to be safe. Is this combo ok or do I need to order the correct counterweight before I use the PC? Thanks 2881