My SGL-21's factory five round magazine wobbles in the rifle, but none of my Bulgarian Circle 10 magazines do. They lock in tight. The polymer feels much nicer to handle than the recycled tin-can feel of the steel magazines. I've been very happy with them so far. Be mindful that if you are carrying multiple magazines in a pocket or pouch, the 'waffles' make make pulling them out a little more difficult than the smooth sides of the steel magazines. However, I'd bet the polymer magazines don't rattle against each other as you jostle them around.
By
Ikeaboy from
Warrenton, VA