I switched once from goodyear to M/T and must say it was the absolute worst decision I have ever made for my race car. The Goodyears I took off the car had prolly 250 passes or more on them and were old. At the time I took them off I thought I needed tires cause they were 250 passes old(they were hooking 1.31-1.32 consistently), my brand new M/T best 60' was 1.34, I ditched em after around 70 passes and put a new set of goodyears on and guess what 1.29-1.31 and they easily last almost 2 seasons on my car with many passes and lots of sidewall abuse(no tubes). Needless to say my car will never again see another tire manufacturer other than goodyear on it.