The Geissele SSA is my go-to trigger for a SD AR.
The ALG ACT is a very good trigger for the money.
Considering current pricing, I'd go with the ALG ACT--I have a coupla'--three Larue MBT-2S's bought back when they were $75 each, and I prefer them slightly over the ALG ACT--But NOT @ $112 each! YMMV, of course...