The Bushnell Elite 15-45x60 spotting scope is very good for $350. The Vortex Skyline 20-60x80 spotting scope is a big scope; an option at $400. I recently looked at the Nikon Prostaff 16-48x65 spotting scope ($400) and liked it very much. I actually liked all three, but would probably go with the Bushnell unless I needed the extra power of the Vortex. You can buy from Eagle Optics and return an item within 30 days for a full purchase price refund. This lets you check a scope out and return it if you don't like it. Another possibility is the Celestron Ultima 65 ED w/ 16-48x eyepiece for $310.
A great value is the Celestron Ultima 80 ED w/ 22-60x eyepiece for $429. This scope is comparable to the highly regarded Pentax PF-80ED 20-60x for $1050.
If you can use a big scope go with the 80mm objective, otherwise if any semblance of portability is required go with a 60-65mm objective scope.