The tire life highly depends on what tire you go with. The OEM summer only tires that came with my car have an average life of 15k miles. I managed to squeeze 19k miles (really hard use, including road tracking and autocrossing) because I rotated lots - square setup.
Michelin Pilot Super Sports (PSS) are all the rave of performance summer tires right now because they have one of the best all around grip of any summer tire and have a 30k mile warranty! It's almost unheard of for a performance summer tire. So really, you are getting an unbelievable summer tire for the price ($1070 shipped to my door for 245/40-19's - much cheaper for 17's).
I've heard not the best things about those Sumitomos. In both poor traction for a summer only tire and poor sidewall flex.
If you consider only the life of the PSS, it's the best bang for buck summer tire out.
With AutoX, you can run a 18x8 or a 19x8.5 wheel and get away with stock class still since they were factory wheel size options.
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2012 Black 3.7L =Performance Package