My choice lpk - Strike Industries AR Enhanced Lower Receiver Parts with Trigger, Hammer and Disconnector

I personally like the Strike Industries LPK. It's a nice medley of milspec and "upgraded" parts. The bolt catch and take down pins have a nice aesthetic look, while still being robust. As other reviews mention the milspec trigger is on the lighter side, I'd guess around 6-7lbs. The main reason I like this kit is the safety. I'm a big fan of not having a 90 degree safety, but this has the option for 90 or 60 depending on preference, as well as ambidextrous if needed. All in all it has several upgrades that I prefer, along with everything else needed to complete a lower.