The best for an AR platform would the Trijicon MRO as far as compactness and ruggedness. The RMR belongs on pistols.

"Saint AR pistol"

Sig Romeo 5 will work for less.

I just put one of the “Justice” model on one of my Glocks and my shotgun. To early to tell longevity but man it’s easy to pick up and adds no weight

I was also looking at the Holosuns


https://www.swampfoxoptics.com/liberty-justice

I know you do a lot of research on stuff...what made you choose this one BIL?

I have taken a high round count (1500-1800 in 3 days) Leo instructor level pistol class the last 2 years. I noticed the instructor ( one of the best, if not) had one on one of his many guns and constantly took it on it off and on with no issues. He shoots probably 50,000 rounds a year. I’m not sure how many he shot with the sight but I knew that number was much higher than I shoot. I briefly looked through the glass and found it to be super clear. At the time I didn’t even know what it was. I was shopping for a red dot. Of course I like a Trijicon rmr but I don’t like the price or the sight picture. I don’t like the glass on the leupold Delta point. The Acro window was to small. I like the Holosun and a few tactical guys are starting to run it. So I found the logo on google and I researched the Swampfox sights. There weren’t many negatives and had the best pricing ( Black Friday). So I bought 3. So far I have one on my 1301 tactical I sighted in with slugs and one on my Glock 34. They also came with Steel shrouds. So for my varmint hunting and range time it was a no brainer. If they hold up I may try it on duty some day. I looked at all of them and I was most impressed with the Swampfox and Holosuns for glass, shake awake, dot clarity, and top loading battery.