It's fast and efficient for loading. Even without a lid or with a lid open balls do not come out.
Weaknesses:
A little expensive. The pin that holds the lid onto the collar came out on mine during a came. I never found the pin but the lid stayed on long enough for me to remove it and put it in a pocket. You have to have a Revolution loader to use it.
Conclusion:
I enjoy my slammer system and I intend to add a harness. It works as JT advertises. Aside from the expense and the lid problem, I like it. Overall it's worth the money especially if you look around for deals.