I’ve check out spotting scopes for years and to this day, haven’t felt the need for a separate optic just for spotting, but I know plenty of people that got their money’s worth. “The Mission Drives the gear” they say and you don’t need to spend money on things that add weight to your payload that you might not need. In the military, optics are on most rifles these days and having 3x-4x can help you get plenty of range, but that’s not going to help you see pinpoint accuracy like whether or not you got a hit at 500yds or if you missed the paper. Some of these issues can easily be over come by using Shoot N C targets but depending on the caliber you are using, it can still be difficult. Another thing to be careful about is in hot weather, the mirage you get from grass and dirt will wreck your ability to see at any range and magnification will just exacerbate the problem. Two man sniper teams usually have a spotter that picks the targets and gives ranges but you can do much of that a good mil-dot rifle scope.
One thing to think about if you are thinking about getting a Leupold or a Bushnell, but if you can afford it, Leupold Optics tend to be some of the best optics out there and if you are an outdoorsmen, you can do a lot with these if you have a good tripod. I’ve often found that the Tri-pod means just as much for Spotting Scopes as does clarity because even some cheap optics will work as long as it’s not low light, low light situations is where you find out how cheap your optic is because an optic that allows more light to go through it will cost you more. Just like rifle bipods, you gotta be careful you get a mount that works with what you need because if it’s too tall or too short, it’s going to be very uncomfortable to get into good viewing positions.