+1 on Garmin's. My buddy has a Garmin on his airplane for navigation and when I was looking to buy one, he suggested that I buy a Garmin. I bought a Garmin Model 76CS, then later bought a Garmin Etrix as it is smaller and easier to carry hunting.
As mentioned above, you should specify what you want to use the GPS for, and that will dictate what you should buy.
I have not compared a Garmin to other makes, so I can't provide a comparison. However, I will be sticking with Garmin's as they are very easy to use.
Martyn