It's time to replace front and rear tires. I looking at Nitto 555II - 305/35 ZR18 for the rear and NT555 275/40 ZR17 for the front. The car is lowered on stock bolts, has stock wheels, and seldom sees rain. Any down side to these tires? To the Nitto guys; what kind of thread life can I expect to get with these tires?