imo the black pads are best for very light polishes or jeweling using something like menzerna PO85rd, i use the red or blue LC's for wax. the difference is the black/gray is more dense then the red/blue. i think i may be switching from LC pads after i try these buff and shine pads i just got, i like them already from the shape of the pad as its an actual 5.5" pad not like lc's that have a beveled edge and dont give you true 5.5"..that and the orange B&S pad is more dense then a LC orange. but yes you heard correct flat pads correct better. just be careful with the lc pads, dont soak them for long, stay away from edges and dont let them get too hot, here lately they have been having delamination issues where the adhesive looses bond with the loop backing.