The hiperfire is supposed to be the new thing. The way I understand it, the problem with standard AR trigger designs is that if you want a lighter trigger pull, it automatically reduces the hammer energy significantly. Actually it's more like to get a lighter trigger, you purposely reduce the power of the hammer spring. So with duty triggers, its not that it is easier to have a negligent discharge as much as the fact that a lighter hammer and cheaper ammo isn't a great combination when lives are on the line. The hiperfire is supposed to let you have a light trigger pull, yet still have a lot of hammer energy. I have not tried one but if this is true then that is very interesting and I'm not sure why they aren't even more popular. Personally I run a Geiselle SSA and it is plenty adequate, I feel no need to upgrade especially based on my skill level, but if I ever build another I might go that route.