There is often a debate on whether or not you need a spotting scope or binoculars when hitting the range. The biggest problem with binoculars is that they are not always that stable. If you have a spotting scope on a tri-pod its going to give you more stability which will mean clarity. Sometimes spotting small holes on paper at 500yds is difficult, even with higher magnification. You can always do what I do and just bring a scoped rifle with you and use that for spotting. There are many things that come into play if you want to see things at longer ranges, mirage from heat, humidity, and sun glare can all ruin your ability to see.
The real selling point I would have for a Vortex Monocular is that they are smaller, compact and lighter weight. You get a very good field of view of 393 feet at 1000yds for the Vortex Solo R/T Monoculars. Being able to throw these in a molle pouch on your plate carrier or even just clip it on to your plate carrier makes it easier to keep around. Target identification and range estimation are the main selling points, the second is that most Vortex optics are priced about $100 below what they are worth. Sure you can use these for bird watching or boating, but this is a tactical blog and this is definitely something to consider.