Sal...you must be using bad air.
Ernie...I only use a plug to replace not having a spare...just to get me home if that sealant crap won't plug it...then I have an inside patch put in.
Morg...Greg at Wheel King will get the guys will do it right...they remember how to grind it nice beforehand. Don't be cheap...tip em. Had them patch one on a previous set that lasted 3,000+ miles. Says alot that only they (and no Goodyear stores in the area) are specified by the local distributor to mount the run flats on the Vette...sometimes takes a 100lbs to get the bead seated...bang!