Is the TAPCO unit single or two stage? I have always liked the two stage trigger system, let's me know just what going on when I pull the trigger.
I know that you can make the RSA FCG either single or two stage but don't know about the TAPCO unit. As I don't have either type, I'm going on what others have said.
I have the Lyman digital trigger pull gauge (very nice) to tell me what the trigger is set at. For my AR15 target rifle, trigger pull is set at 3.5 lbs., first stage is 2.5 lbs, second stage 1.0 lbs.
My DCM AR15 match service rifle is set to the legal 4.5 lbs., first stage 3lbs, second stage 1.5 lbs.
Both of these are for target work, for anything used in a combat/self defense type mode I would want at least a 4.5 - 6 lb pull (maybe closer to the 6lb weight).