I don't use one, I generally just step things off, if i'm close to chart I'll get out a 100' tape measure. For things up in the air that are hard to measure, I just use the rusty mark I eyeball, and I'm usually pretty close.
Last rangefinder I was around, a guy came to meet me at a project and we were talking distances, and he pulled it out and proceeded to tell me to the 1/4" how far something was away. I looked at it , and looked at him, and looked at it again, and the rangefinder was nowhere near close. I'm not perfect with my eyeball, but I usually can get pretty close, and the guy wanted to argue about it. Life is too short for that- I'm willing to agree to disagree.
I think the biggest problem with rangefinders is getting a accurate surface to bounce it off of. Trying to stand on the ground and bounce it off a cell tower is a waste of time. All that round pipe doesn't give a good reflective surface.
I do think they have advanced a lot in the last few years, and they have come down in price a lot. If I was buying today, I'd probably end up at a sporting goods store looking for something from the bowhunting department. You don't need 1000yard accuracy. You need 150' accuracy, and that's bowhunter range. Plus the hunting gear tends to be robust, and able to handle a little rain or being dropped.