Before I start about thermals at all, Id like to notice that clip-on sights are very smart and useful. Tons of problems are gone with them, e.g. like numerous mounting in and off your day scope in case u r going to night hunting, of course if u dont have 2 same rifles, which I think is not very smart. At the very outside you can use it as a monocular, pretty expensive monocular though.
Thermal is a separate matter. In opposite to any of the night vision you can use thermal scope any part of the day, and even in total darkness with no additional sources of light like an IR for example or your own pair of eyes, if you hunting a bear and scared as hell. No need in that at all. Even a turkey wont be able to hide from you behind the bushes or grass, as its heat will disclose it anyway. No problems with magnification as well, my Leupold Mark is 10x and this clip-on doesnt limit its capabilities in any way. So no chances left for any creature alive with this beautiful Armasight thermal clip-on.
This review was written in the old system and had content requirements that are different than reviews written today.