As a prior training officer for a fairly large sheriffs department, we used a heavy blue gun for training. I can’t remember who made them, but I believe we got them thru Galls. They were the exact size, shape, and weight of the actual weapons we carried on duty. I never used real weapons to train with for weapons retention, and disarming techniques. I didn’t use them because, because metal has way less give than your hand does and injury is not a likely with real weapons but a certainty. Make no mistake you can get hurt with the plastic guns too but they have more forgiving on the hands just don’t keep a finger on the trigger or it will get broke. Also the training weapon will be dropped and thrown during the course and me personally, I don’t want my pistol being thrown around hitting the walls and floor all day. I don’t have any experience with the light weight red guns mentioned but using a training gun the same weight and size of actual weapons would be better for you, you may not think so at the end of a long training session but you will if the need arises in the field.