at less than $100 I was crazy to NOT try this option. bought adapter and mounted on S&W M&P40 to see if pistol rds was for me. easily installed and looks nice. Took it to the range yesterday and it does as it says: a dot which is red. Zeroing proved to be a hassle. the provided screwdriver did not fit through the adjustment wheel as described so I was forced to eyeball adjustments. In addition, there is no "click adjustment" just a continuous spinning windage and elevation screw. These did not hold the zero well at all! the most I was able to get it to hold was about 20 shots. After I noticed the POI was off, I looked down and noticed the screw had rotated during firing. Just to make sure, I kept firing groups and watched the elevation and windage offset increase up and to the left. This was a constant problem. definitely got what I payed for but it served it's purpose. The easy target acquisition made it all worth while. I know I will be sticking with an RDS just not this one!
Pros: Easy install, easy use.
Cons: adjustment / zero. no auto on/off
This review was written in the old system and had content requirements that are different than reviews written today.