As far as a Reflex sight, cannot add any input but on my Ruger MRIII Hunter, I had a Red Dot scope on it for a time and loved it....spot on and has the red/green dots on 5 different settings.
Some you will find, only come with the 5 moa (dots) and they will basically cover a pop can out at "about" 30-40yds.
My preference on a (dot), would be something (smaller) than a 5 moa dot.
As far as color, I use both the red and green when I had it on the MKIII as per background color and or, target color/background and time of day shooting. (cloud cover/sunny, etc.,)