Premium trigger in case you want a drop-in - Elftmann Tactical Trigger AR-15 Match Socom Adj 2.75-4lbs.

I can't think of a drop in trigger with a better reputation for being easy to install and great function. Adjustments are now super easy as well as seen by the big silver adjustment knob - you don't need to disassemble stuff to adjust your trigger. I run a Deadfoot Arms folding stock system and so the Geissele triggers are not compatible