There seems to be some difference of opinion about whether #83 or SSR2.5 has more cut. That issue aside, I recently did a side-by-side on the hood of a black car and SSR2.5 seemed to finish clearer. I should qualify that by saying that I was using different pads, an old-style Sonus Orange with the #83, and a CMA Constant Pressure yellow "compounding" pad with the SSR2.5 (which theoretically should have finished worse than the orange pad).