http://www.crank-scrapers.com/

I have one of these, but I have not installed it. Not sure it'll work with my NISMO pan which has some windage stuff built in as well as a rudimentary scraper.

If you read on that site and others it appears that folks can see a couple percent gain, although I'd expect that to be limited at some point. If you have a 1600 hp motor 3% would be 48 hp, but does the 1600 hp motor benefit from oil control that much more than a 200hp version? I guess what I'm trying to say is there should be a limit to how much hp you can gain with one of these in my opinion.

There are more than a few OEM cars that use them. Porsche has them in the bottom of a few pans, as does the big three on some engines, and in some Japanese cars as well. If they spend the money to do it then it is probably worthwhile.

Ron