i have gone thru several rangefinders.
if you want the best, go w/ a leica 1200.
if you want the best for the money, go bushnell.
i've gone thru one simmons, one tasco, 2 bushnells, and have worked w/ the leica... because you are asking this question, i assume the leica has already been ruled out.
first, the simmons... was rated to 800 yards. would actually range to 150-200 yards on a prairie dog town, and was erratic in doing it. lots of erroneous readings. same goes for the tasco (i suspect they are made by the same people, because they look the same, and neither one works).
the bushnells... really work nice for the money. i think nikons and bushnells are made by the same folks, but different people than tasco/simmons. anyway, had a bushnell 400 first. would consistently ready to around 340 yards on a dog town. occasionally more, if the conditions were favorable.
the bushnell i use now has long been discontinued: compact 600... operates on a 9v battery, and came w/ a nifty neoprene case. simple operation, and quite accurate. have gotten readings from trees and grass out to 800 yards - though it is inconsistent at this range. inside of 600 yards, it works well, and inside of 500 yards, it works extremely well.
optically, the glass sucks on every laser i've peered thru except the leicas.