I think rangefinders are valuable for very low handicappers. I think players of all skill levels might benefit from a simple GPS -- one that can provide front/back/middle instantly at a glance. Pin distances, like those included at some high-end courses on carts, are a bonus.
Either device type should speed play for most. It eliminates hunting for sprinkler heads and/or pacing to markers. If it takes more than a few seconds to get a yardage, then the device isn't right for the player.
My guess is that some of the opinions here are biased by skill level and course familiarity. As skill goes up and familiarity goes down, the value of a device goes up. Elite players who can afford them will want the best.
I used a small GolfBuddy GPS until I forgot to remove it from my pocket before laundering. I'm turning 60 next week and, now that I'm retired, was thinking about gifting myself a good rangefinder. We just moved to a retirement community that has 9 golf courses over very hilly terrain. I'm a low handicap and was thinking that a rangefinder with a slope option would be invaluable. I've only looked at some in a sporting goods store. Kind of agree with the poster who liked the Leopold optics (my eyelashes did not interfere with image) but the Bushnell features and quality seem hard to beat. I'm considering the Tour X model but have not had a chance to actually see/use one. I liked the fact that the slope feature can be disabled for tournament play.
I'd like to hear from someone who has a low handicap, plays on hilly terrain, and uses one of the higher end models. Are there different opinions out there as to the value of the slope feature, or is it infeasible to get an accurate effect? I would think that the player's ball trajectory might play a significant role, but I have no experience to know. What might be more important to me is the ability to lock onto the pin quickly with a shaky hand. I'll probably be holding my glasses in one hand and the rangefinder in the other. I'd also like to pan distances to bunkers, trees, and other objects.