Danny, I have seen drivers from both USAC and winged circuits race the Boz stuff online. Drivers that I know of including some lesser known drivers are:

Kyle Larson
Brian Brown (Brian Brown's crew chief Chad Morgan runs too)
Kevin Swindell
Chase Briscoe
Aaron Ott
Amy Ott
Dylan Cisney
TJ Hartman
Nick Cooper
Chris Gerhart
Steve Wilbur

I know I am missing a few others but some are guys who run winged 360s, 410s and some wingless stuff with some others being micro and mini sprint drivers looking to move up. These guys are fast but fun to try and beat.