I think they work very well, at the last match I attended, I removed a dry ball For a younger shooter. Works like a champ, only problem is the CO2 leaks down over a long period of time and I have to always put on a new cylinder. But in this case it allowed the fellow to keep on shooting without have to give up that morning. I think they really have their own place. A grease gun would have worked, So would probably an air compressor, But neither was available on-site. I would've put a charge under the nipple, but he didn't because he didn't know why it wouldn't shoot and didn't know it was dry balled. He thought he might have even double loaded. The only reason I've ever dry balled was because of visitors.
Squint