IMHO 4/5 mts accuracy is a very good accuracy for a gps and accuracy may depend on many factors (Surrounding conditions ,satellite visibility and multipath:Number of satellites in view, ionospheric conditions etc) - To make [Only registered and activated users can see links. ]you should compare 2 devices put in the same position at the same time and conditions.
Many users complaints about 37xx-->34xx gps accuracy, I havent found significative differencies between the two versions, especially using it on the road driving, nor comparing 34xx ,in the same conditions,to my 1200.
Garmin's web site itself states the following: "Garmin® GPS receivers are accurate to within 10 meters on average."