I must be the oddball here. I play with both and actually prefer my GPS. I use the upro and appreciate the fact that I can get exact carry distance to front/back of greens, hazards etc. I like that it shows me the exact shape of the green too. It's also nice to know how far you drove the ball or hit your 3 wood from the fairway when you use the mark distance option.
I am lucky enough to be an avid hunter so I've also got a really nice Leica range finder. I've carried it before and used it to see how accurate the GPS is and found that the GPS was right on as far as yardage. While there is a little estimating exact pin placement I can get within 2-3 yards with my GPS when you know if the pin is front/back/middle. I found the GPS to be faster than the range finder. Just hit a button and results are instant. You still have to sight through a range finder.
Both have pros/cons but I prefer the GPS.
FYI, as far as range finders go, I've owned Bushnell, Nikon, Leupold and now a Leica. There is absolutely no comparison. Leica has the best glass around and that really makes a difference in shadows. And the 7x makes it easier to see the pin from 200 plus yards. Never had a problem problem finding the pin but then again, it can range a fence post at 1000yrds.