If you get an alignment contract (NTB does 5 years and Firestone does lifetime), then you can just go get one whenever you feel like it. I drove mine hard enough that I needed new rear tires about every six months - I got an alignment every time.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |