What's the best gps system to buy for a car?

I’ve been looking into buying a GPS system for my car. I don't have a lot of money though. What’s the best one to buy?

I don't know about the best one but I've been very happy with my Garmin iQue 3600. It is a PDA GPS that runs PalmOS. Every address I have in my address book is available to route to which cuts down on the amount of data entry.

It isn't perfect. I let it route trips I already take and it sometimes comes up with less efficient routes than I know but on the other hand it would get me there. Sometimes instructions are confusing but the good thing about using a GPS is that if you miss a turn it automatically reroutes you to your destination from your new location. There are a few new roads near me that even though they have been here for a year are not on the latest maps.