[Dinsdale]

Never used soap or screws on a 650ish HP bracket car. 3200# and a stick. Some tires just hold air and others don't. My Goodyears were great, Hoosiers seem okay and M/T's not so good with 1 tire being worse than the other. Unless you have a tire machine and balancer handy (I don't) then doing a back to back comparison isn't reasonable.

As for screws... I put my tires on dry and find that all three brands move about an inch and then stop. Pretty sure rim selection makes a difference here. If you run tubes then you need screws otherwise the valve stem will tear off the tube when the tire turns.