I'm looking at possibly ordering the Vortex Viper HD 15-45x65 spotting scope. Have any of you had any experience with this one? Is there another option out there in it's price range? I've never owned a spotting scope but I have always wanted one and, despite my love for them, my Leica 10x25 binos are slightly inadequate for long range work. Right now I can get this one with a straight eye piece for under $600 shipped.