I have a few questions because I’ve never owned a thermal before. First, I’m looking to spend $2-4k on a scope. Would like to keep it in the 3k range if possible. I like the idea of the rangefinder on the AGM Varmint 50-384. But I could buy a 35-640 Rattler without the rangefinder for not much more. Is the rangefinder more useful in the thermal world or the 640 resolution? Also, is the 35 or 50 more useful? And why? I will mostly be hunting 300yds and in, but really value long range capability, as I have some long range spots and also just like to check things out at distance. Another requirement is to be able to remove and re-mount easily and maintain zero because one of the main uses would be as a handheld to show my 6 year old the different creatures at nighttime. I have also considered Bering optics. I am open minded, but want the best optic in this price range. Also, I need recommendations about reputable places to buy whatever is recommended and at decent prices. Please help and thank you in advance for your consideration.