The real issue with any GPS is the data that it depends on. If a data set is not accurate, the route you recieve may be flawed. Like telling me to turn at TRAIL. Most of the makers actually do some sort of verification of the data but it seems to never be 100%. I think there is a dependancy on existing maps and other forms of satellite data that are combined to produce the data in a GPS.

I can say that I am content with both of the Garmin vehicle GPS units that I have, although they are not perfect. The newer one, the 2555LMT is a big improvement over the one I used up until this past summer. I have not had a fault with it so far. I have not tried other brands and they may, or may not be the same or better.

One thing you can do is add POI's from sources like Google maps and those have often been inaccurate in the navigation, so take that for what it is worth. I also added the City navigator software for San Diego and LA last year to my old GPS and although it adds loads of POI's, it is also much more cluttered if you are tryiing to get to a specific place. Too many points available can be probematic too.

Good luck in your quest, I am sure you can find a good GPS for a good price, they keep getting better and cheaper.