Things I liked: Great fit in the barrel, held a quarter sized 5 shot grouping at 30 yds indoors.
Things I would have changed: They need to have more weight. I bet a 10mph crosswind would throw these off by 6+ inches within 40 yards. I get the feeling that very little air pressure builds up behind these in the barrel, as the only thing that holds them snug is the little bit of plastic fin that makes the seal. Does not fit snug and utilize the rifling in the barrel with the actual pellet.
What others should know: Accurate pellet and decent penetration. I compared these to the copper gamo pellets. The copper pellets outperformed these. Similar accuracy, but the copper pellets had a considerable bit more penetration. I would NOT recommend these for hunting. I nailed a large robin with one of these, and it RAN off (couldn't sustain flight). It's initial reaction was to attempt flight with a 3ft flop in the air. Very inhumane in my opinion, has no knockdown power nor does it create a significant wound. Head shots or heart shots only.