Windage trays / crank scrapers

Do these actually do anything on anything less than a full blown track car or truck? I get the theory of operation but it seems like something you'd want if you're chasing tenths instead of if you're tooling around on the street. I have an oil and water cooled turbo and I was wondering if either a windage tray or crank scraper would help keep the turbo oiled and cooled, as extra extra insurance on top of an oil cooler. This company sells them for Sirius engines:

http://www.crank-scrapers.com/Mitsubishi_g63b_4g63.html

There seems to be a raging debate over the usefulness of these things everywhere, the DSM community especially. Any input? Hopefully Rahtid, Merrill and LSR Mike will chime in.

EDIT: I meant to post this in Performance Mods. Sorry.

They will cut down on drag caused by oil buildup on the crank. I have one for the turbo 2.6 motor I am building for one of the trucks. It will mostly help at high rpms, not at normal street rpms.