I ran the old 3.2 sized ones, but I taped the foams, not the tires. Whenever I taped tires, the tape would come loose then get out of balance. By taping the outside surface of the foam, your at least helping with ballooning to keep the foam from expanding. I do this whenever I'm mounting new tires on my MT's or baja. Seems to work pretty good and have never had the tape let go/get out of balance on me.
I ran a set on teh front of a sport max for a loooooong time and I still have them on a shelf with decent tread left. Granted, I spent about 50% of my time in the grass, but the other 50% was in a concrete skatepark.