I recently purchased a Garmin GPS and more specifically the nuvi 2597LTM, 5" screen. Compared to other makes, I find Garmin to be the best GPS devices out there for all sort of reasons. I have used different models of Garmin GPS over the years and I was fully satisfied with them every time.
However, my recent purchase put me off a little bit and the reason was that I was expecting more from Garmin. What I mean is that I purchased one of the latest models in 2014 and I was expecting to see the graphics to be a bit more smooth, without any delays in drawing/redrawing the map. It feels like they haven't upgraded the processor over the years and its performing exactly like a GPS bought at least 6-8 years ago. Also, it would be really nice if the screen had better resolution. We have retina displays now, I don't think increasing just a little bit the screen resolution would make such a bit difference to the final price. Despite the above the GPS is picking up the satellites very fast, the antenna picks up the satellites in semi-covered places as well, the real directions are very nice and useful, and of course the bluetooth allows you to take calls on the GPS which are loud and clear!
The issue I had to face though, came a couple of months after during a trip. The GPS decided that the auto-brightness feature will start working as it pleases. More specifically, during the trip, it decided to switch from bright to 10% brightness. Every time I set it back to 70%-100%, after a random number of seconds/minutes it switched back to 10% for no reason.