one of the houses i frequent, returns balls from pit with thick black belt marks which are pain to remove. With my current cleaner, which is good, but not strong enough to really get it done. I have to really put some muscle into it. Only when I get home and use CnD or LMB, do I get it spotless.
we can see these marks on a LT-48 or any black ball. Really horrible when these thick marks are on your ball track.....
I have to inspect my ball as it returns and spend my time in the back table rubbing the crap out of my ball. I burn more calories cleaning my equipment than I do bowling.