I just spent a few days and bunch of ammo testing a Swampfox trigger group. The review is on my blog here: https://1022companion.wordpress.com/2015/08/30/swampfox-trigger-review/ (https://1022companion.wordpress.com/2015/08/30/swampfox-trigger-review/)
Bottom line: I love it. Now, you don't need an upgraded trigger to score Rifleman. I've done it many times with an OEM trigger. But a great trigger is much more fun to shoot, and easier to shoot well. This modified Ruger trigger group is a great one.
Thanks for the great review. How would you compare with Brimstone tier 2?
They are very similar. Brimstone Tier 2 is a little more money and does a little more refinement of the working parts. Brimstone Tier 2 also offers only the Rimfire Technologies replacement trigger. You can save some money compared to that by having Swampfox modify the OEM trigger for the torsion spring - with the basic job and torsion spring kit, that's a $60 job including shipping. (Swampfox can also add an RT trigger for $20.) When I priced both from their websites, the directly comparable jobs were within a few dollars difference including shipping.
Swampfox also occasionally has complete, modified trigger groups for sale, which Brimstone does not. He advertises them on the Trading Post section of rimfirecentral.com