I've used/had Bushnell 800, Leupold RX IV, Sig Kilo 2000 and Leica 1600b.

I own all but the Sig. (Friend has that model)

The Bushnell is good for the money. Will range a deer about 400 yds on good day
Leupold is IMHO the worst. It's a 1500 yd rangefinder and struggles to range deer out to 500 yds

I did a review of the Sig and Leica on here. If I recal correctly the sig ranged every bit as far as the Leica. The Leica was easier to pick up targets due to the size of the sigs reticle (if sig would reduce the reticle a bit it be a home run in my opinion). The glass on the Leica is better as well. Sig has blue tint making the Leica a better for low light.

In that price range id really look at the bushnells or sig. If the reticle is better on the Bushnell (like the model suggested above) I'd get that. The sig is a good choice to but after using it a bit you need to use the scan mode most of the time to pick up deer at long ranges. 700+ yds. Again due to the reticle size. That's just my $.02