There are several good units out there but it depends on your purpose. My friends and I have a range of differnt models and the Nikon series is by far the best. The Bushnell are ok but highly misleading. They invented the reflective non reflective jargon and do so to their advantage. While one of their units is good to say 600 yards reflective a realistic distance is about 2/3 of that. Nikon uses the distance that you can range an actual target.

Bang for your buck (ha ha) I recomend the Nikon 600. It will range out to 400 or 500 yards on just about anything and is really small.
I just upgraded from a 600 to a monarch 800. I also long range target shoot and wanted the extra couple of hundred yards max.

If you want to spend more the lieca etc are really nice but larger