I have a rail master on the bulk of my ARs. They are not ATPIALs. But they work in the same scenarios. You just have to understand they don't hold up to abuse, and it also serves to advertise your location. If it's an RDS or laser, I'd choose RDS. If it is RDS AND laser, and you have the funds, and desire, who the fuck am I to talk you out of it. It has a niche role, and works well for engaging targets in less conventional shooting positions.