I have whatever the base model is that garmin offers. It works great in areas that haven't been changed in a few years. The only places where I have encountered any trouble is Houston and Dallas. I have driven with it in Texas, Oklahoma, Kansas, Missouri, Illinois, Iowa, and Indiana and those have been the only two cities that have given it any trouble. I didn't have to pay to download any of the maps for it. I find that it still helps to look up directions before hand and look over them just so you have a basic idea of where you are going and then keep them in the glove box just in case your GPS tells you to do something crazy.
but for the most part it gets you where your going? I might invest in one of these bad boys
"Why do you need so many snakes?"
"Why do you need so many shoes?"