The higher powered binoculars are specialized, like I said. Their big advantage over a spotting scope is that you can glass with them. Spoting scopes work fine for getting a better look at something you've already seen. But for finding something you can't see at all, nothing beats a binocular.
The other thing I'd point out is that the 12X class don't really come into their own until the range opens up to the 2 miles plus range. That's not to say you can't use them like a spotting scope closer in, but their real advantage, like any binocular, is to help you find something you haven't already seen. E
