I don't shoot a lot. Maybe a couple hundred rounds a year. Could be how I adjust them. All know is I like how they feel the way I have them set up. The problems in the past were doubling or trip/quaddroopling. The most recent problem was when I took a Jewell trigger out of a lower that wasn't being used and installed it. Adjusted, function tested it using my fingers to catch the hammer and reset it and then went to shoot and sight in. Had problems from the get go. Would fire the first round and chamber the second but the hammer wouldn't reset. It would just follow the BCG home. Function tested usingy finger again and no problem. Function test by pulling the charging handle back. The trigger would set. Pull the trigger to drop the hammer. Kept the trigger pulled while I operated the charging handle to reset the trigger and NO GO. The hammer would just follow the BCG home. Started to trouble shoot. Adjusted trigger, same problem. Changed BCG and tested, same problem. Changed buffer and spring, same problem. Changed uppers, problem went away. Thought maybe it was something wrong with the upper. Put that upper on another lower with a Jewell trigger and no problem. Thought maybe it had something to do with the lowers pin holes being a tad out of spec. So I pull the Jewell trigger out of the lower that was having problem and switched it with the one in another lower. NO problems when function tested. Thought maybe it was the trigger. Put the trigger into a different lower. No problem when function tested. They work and feel great for a year or two (but low round count, maybe a couple hundo) and then something goes wrong and I start to have problems. At thus point, I'm tired of messing with them. Tired of having problems with them. And frankly, I just don't trust them anymore. Hope this rambling made some sence.