I have y2k cobra wheels on my mustang with nitto 555 extremes on them. They are starting to wear really bad and i'm a broke college student. I'm wanting to buy some cheaper tires this time around. What are the major differences between 265-35-18's verses 245-40-18's. The 245's are way cheaper than the 265's but is it really worth paying the difference for them. I was thinking about getting the kumho supra tires in 245-40-18. Are these tires any good. Also how do you know which tire is lower profile? thanks