Good stuff in this thread. I too use a Garmin Vista Hcx and it rocks! I can lock signal anywhere, like sitting in my office.
One other thing I would suggest. If your unit uses AA batteries (most units do) buy and use lithium batteries. Yea, they are a little more $$$ up front but they run longer, are lighter in weight and are less effected by the cold (battery killer #1). I have been eyeing the Garmin Oregon (400T,550T,ect) series. Anyone own/use? Looks like a cool unit!
Regardless of which GPS unit you carry, buy a quality compass and learn how to use it. A GPS can become uncalibrated (it happen to me once...) and things get interesting when it's pitch black and it say's your at your waypoint but in reality your still deep in the woods.
JL