Are they all the same objective diameter? Same eye piece? 20-60x 65mm I’m assuming.
I much prefer the Angled spotters for phone scoping, which is basically all I do now.
STM offers weight savings and is HD. I’d probably make an offer on that one. Resale value on this one for backcountry hunters if you ever sold it is very good too.
Light gathering even from an 80 will far exceed a 65. Just an FYI. Did that test too.
If you’re willing to be patient, there are good deals on these spotters. Just be ready to buy it right then and there when it pops up. I won’t mention numbers here but Pm me if you want prices for what I’ve sold spotters for in the past to give you a guide.