They seem to have done well enough against other cars when lap times are compared. And it has done very well in ALS as well as SCCA.

Honestly though, the power to weight, as well as available traction of the go kart is much higher. Top speed is limited, but it has good acceleration, braking, and cornering. Also, because of the go-karts size it can use much more of the track when cutting the apex so it actually needs less grip to maintain the same speed because the corners aren't as sharp. I don't think I've ever seen a video where a shifter cart hasn't beat a car on a small track. Small tracks favor small, lightweight cars because there isn't enough room for the heavier, more powerful cars to stretch their legs. But put a cart on a large track like Road America, Road Atlanta, Sears Point, Nurburgring and the larger, heavier cars will win because of their higher speeds.