My carry pistol has a red dot, Romeo1Pro, 3 MOA. I'm a reluctant convert, but convert I did because I sell so many to LEOs. Figured I should be able to speak about the product w/ more than theoretical knowledge. It took me about 700 ~ 800 rounds before I became a believer. I continue to train w/ it and improve.
In the medium to full frame gun optics:
Trijicon has the best rep, but the RMR has a smaller field of view than its competitors and a bottom mounted battery.
Leopold is a solid optic, but they're the tallest of that form factor requiring extremely tall sights (and limited selection) if you want to 'co-witness'.
Sig is coming on strong. I would avoid the original Romeo1 for daily carry (poor battery life) but it's fine for range toys. The Romeo1Pro corrects the battery life issue and has a more standardized footprint. The commercial guns w/ optic mounted don't come with the protective shroud that the LE guns ship with, but that's an easy aftermarket add on for $40. If you buy a Romeo1Pro optic separately the shroud is included.
The spoiler in the field is Holosun for features and price point. They're so good that Trijicon had to sue them for patent infringement.
![Wink ;-)](./images/smilies/icon_wink.gif)
(since settled we're told).
In the micro optic for micro gun range...just realize there's a lot of technical hurdles to overcome.
I'm most interested in the new Holosun micro optics, but the new Trijicon RMSc will be hard to beat. The 365 XLZ w/ Romeozero mounted makes for an easy package w/ acceptable price point.
There are certainly other brands out there, but I have no experience w/ them and they haven't made the cut w/ the agencies I'm familiar with.
LTC / SSC Instructor. NRA - Instructor, CRSO, Life Member.
Sig pistol/rifle & Glock armorer | FFL 07/02 SOT