So tires will be a consumable. And if you have the 18s, you've got a pretty high performance size of tire, so they won't be cheap.
My philosophy is this--since that small patch of tire is all you have between you and the road, make it the best you can for what you can afford. I got General Altimax Arctics for winter (wonderful!), and Bridgestone Potenzas for summer (yet to be put on).
I don't expect either set to last very long, but I expect each to do its job--keep us planted, safe, and the driving experience fun.
