Go with the Garmin 255W or 255WT, they are both able to be purchased at a cheaper price sine he new models have started coming out. I had the 260W and now have a 1300T. The "T" stands for traffic, which is only in the 50 major US cities. So unless you live in one of those that shouldn't matter.
Don't go with Tom Tom. I work in a major retail chain and we see more of them returned than anything else. Yes they are cheaper, but you get what you pay for.