I just put my first JP in an AR a couple of weeks ago. I used the the trigger that has to be fitted to the gun. Put the Laptop on the loading bench, followed the video, and life is good now.
First time, I took it slow, and it took about three hours, but I'm pretty sure I can do it in an hour now. It was really interesting learning how each piece was a partner in the total operation of the trigger assembly.
I've always used Timmney triggers on all of my bolt guns in the past. The JP is just as good.
I have another JP trigger coming from Make Ready as we speak for a Spikes lower I recently came by.