A spool is a absolute engagement of both tires. If u look at Jeg/Summit you’ll see, there’s nothing to them. Thats because they lack the cluches, ect. to differ the traction to the needed wheel. A spool is a real pita on the street as well. Esp. if u have any kind of power…you’ll be going around a corner in the rain and slide the ass out without trying. Yeah, it can be fun…but, not when ur trying to pull into busy traffic.