I get the same slippage with my AC "N" stall...through the traps at 6050 RPM...128-130 MPH...28x9 slick...which is really a 27" tire...as for 10-12% slippage not being so bad...I guess to each his own...but I think it sucks..I know you said in that "price range"...still sucks IMO...that's why I just ordered a PTC...