This is my favorite trigger! - RISE Armament LE145 Tactical Trigger

This is my favorite trigger. It's a little on the heavy side of pull compared to a lot of other triggers but I like that. Another reason this trigger is fantastic is because it will fit almost any AR lower. The hammer is a little small for the large & XL-frame AR's but it can still hit the firing pin without trouble. The hammer also has a halfway setting if you want to store the spring mostly depressed but not resting on the firing pin.
I haven't used any other triggers so take my review with a grain of salt.