Just to keep each install consistent, I ran another 200rds today with no problems. Each of the three installs had 400rds fired with no problems. The reused factory trigger pins are holding so far in the two installs, and my hunch is it they will hold just fine for the next several thousand rounds. The trigger in each of the three installs is almost as good as my Shadow Orange and my two Shadow 2's. that's my opinion and I will stick with it. Other forum members should not criticize or make comments on the kit unless they have actually installed the MCARBO kit in their own CZ75b's.
The MCARBO kit is a spring kit. Honestly that's it. It's no miracle that it would make your trigger pull lighter. The laws of physics dictate that that if you put lower tension springs under the hammer and firing pin block that you will get a lighter trigger pull. You could take the factory CZ hammer spring, cut 2 coils off and experience a similar result. So your results are not surprising. They are to be expected.
What you continue to (and in my opinion purposefully) overlook in your review:
1. The hammer spring - it is of unknown weight so if you are trying to tune your gun to your liking then you are unable to as MCARBO does not sell differing weights. This is sort of a one-and-done scenario. If it happens not to work with the modifications in your gun then you're out of luck.
2. When you work on the trigger you should replace the trigger pin. Your "hunch" that it'll be fine is just that. I have seen broken trigger pins before but certainly have seen many more broken trigger return springs. In order to service the trigger you need to remove the trigger pin. Even if you have the tools to re-flare it, no one recommends it because flaring it causes weakness. If these are range toys for you, you may do just fine on your hunch. I won't judge that. You can feel free to do that.
However some people carry these guns for self defense. Other people compete with these guns. I would recommend that those 2 categories of people absolutely replace the trigger pin with a floating pin. It's $13. I have seen someone with a broken trigger return spring (and no ability to remove his factory trigger pin) at a match. He tied the trigger to the trigger guard with a rubber band in order to shoot the gun. I bet he wished he had that $13 pin that day. Plenty of us had spare trigger return springs to lend him.
3. Use a starter punch. You saw yourself what damage and trouble you can get into without the proper tools. I've damaged one of my guns as well and learned my lesson. So I tell as many people as possible to prevent them from making the same mistake. Instead you continue to review this MCARBO kit and ignore the problems you've had with the spring install.
While MCARBO does not claim to replace the trigger pin, there is no disclaimer or recommendation that someone should...nor a disclaimer or recommendation that one should use a proper starter punch. They should state that with their spring kit: that there are tools necessary for a proper installation. If they don't, whoever reviews this kit should state that so that others don't get into the same trouble you did.
A bunch of us told you these things and you ignored our recommendations. We didn't do it to criticize you. We did it because we have experienced these problems before and didn't want to see you experience them as well....and then you had your problems. 1 out of 3 guns isn't too bad but it's not too great either.
So I'll be frank here.
I appreciate your review of the kit and the pictures of the range testing. That's effort and not enough people do that.
From your insistence or stubbornness to heed people's advice I wonder if there is some sort of relationship between you and MCARBO...though I could care less of the conspiracy theories. Maybe you just don't like taking advice I dunno.
I have modified many CZ's. I have learned a lot from people on the forum. I appreciate when people explain their reasoning. I have tuned many CZ's and have played with differing spring tensions. What makes a good trigger is not simply a hammer spring and a firing pin block spring. I have worked several guns with triggers under 2 pounds and they are terrible. I have many guns with triggers in the 2 pound range which are incredible. A hammer spring and firing pin block spring only gets you partway to a really nice trigger (if that's what you're looking for).
Shadow Orange and Shadow 2's - These are not simply lightened springs. They have different hammers which drastically change the trigger feel. If you're just talking about trigger weight, then sure you can drop your CZ weights as low as you want. Unless you change the hammers on the 3 guns you installed the MCARBO kit on I highly doubt you are getting the same quality of trigger.
I have played with many CGW Race Hammers and Ring hammers. S2 hammers, two CZC competition hammers and they far outperform the stock hammers.
That may be personal feel but to me it's pretty obvious side by side.
Anyway good luck with your guns. I hope they treat you well and you enjoy your kits. End of the day we are all gun owners who like to play with our toys. No need to get worked up about this stuff.