Interesting reading and I respect what you're doing Dad_Roman.
I'm in my mid 40s and I remember when Glocks and striker pistols first hit the market. Learning a DA/SA took some practice and you learned to feel the trigger.
I'm glad Apex did the engineering and perfected the manufacturing to mass produce their parts and kits. It shows me that S&W chose not to continue engineering the sear and plunger further.
I believe Apex makes a healthy profit on each part and every kit. I applaud that and they deserve every penny. What you get for your money makes a great trigger system for a small total investment.
Its also freedom. People can choose to just put in the sear and some time polishing, or they can do an aluminum trigger, or a whole kit. Spend as little or as much as they want.
Its a great era when you can get an amazingly reliable and quality pistol for such a low price. Great warranty and excellent after market products to make it suit your tastes and needs.
I do get a kick when someone tries the Apex sear and feels the difference.