I think one of the biggest issues with spotting scopes in the lower price range, such as the Vortex 20x60x60, is knowing how to use one. I spend hours on end glassing with scopes, and if I were to put my eye up close to the eye piece, I would be suffering a blinding head ache is less than 30 minutes, and I would miss that little piece of antler sticking out from under a tree in the shadows.
Which takes us to proper use, or how to correctly use a spotting scope, especially at higher magnification, or magnification above 15x.
When I'm teaching someone how to glass with a scope, I teach them to look at the eye piece, not into it. Think of the eye piece as a T.V. screen, get back from it, and view the small dot sized image quadrant that's visible, not the entire available field of view. Regardless if I'm working long hours at long distances glassing for game, or if I'm trying to see 22 cal bullets holes at 500 or 600 yards, I position my eye a good 6" or 8" away from the eye piece, then I roll around the available field of view by moving my head up, down, or side to side until I've covered everything in that field of view, or the specific object I'm viewing. This prevents excessive eye strain, but more importantly, it improves the image quality immensely. But because it's necessary to back way off the eye piece, it's also often necessary to have some way to shade your eye, and the eye piece. For that, I usually drape something over my head and the scope, this blocks out reflections and glare.
GS