Mostly a lot depends on what game you want to hunt and how much weight you want to lug around for how long. In any case, it will be useful for you to study this thermal scope www.atncorp.com/thermal-scope-thor-hd and choose the best option. I do appreciate that brand
One is “best” in terms of resolution and accuracy. I don’t really know which is best by that standpoint, since the high-resolution, high-accuracy thermal cameras are way, way out of my price range. I suppose you wouldn’t go too far wrong with any of the higher-end cameras, like this one - FLIR T540 Professional Thermal Camera
The other kind of “best” is the kind that (a) I can afford, (b) is adequate for my purposes, (c) is rugged enough that I don’t worry excessively about dropping it, and (d) is convenient enough to carry that I can always have it with me.