I've never owned one but I need to help a friend. He has a DDI 47S and is wanting to add a red dot to it. It appears, from my very limited knowledge that it has a sight mount on the left side of the receiver. What would be a decent mount to go with to add a red dot to it?
RS Regulate is considered to be about the tops. He can go with a two piece model which has a lower that is the part that clamps to the side rail and an upper which can be a picc rail, 30mm ring, optic specific mount, etc. They also make a one piece that is just a rail. Arsenal also makes a decent 1 piece picc rail mount.