I have a CZ 452 that I have had for quite a while. The trigger wasnt all that good when I got it. I put in a spring from the spring kit, and took it apart and stoned the mating surfaces. Now, I dont know that I would want the set trigger. The set trigger is slow, but from a rest it probably doesnt matter. Standing, it makes a big difference. If the single stage trigger is good enough on your 453, you can ignore the set trigger except for special occasions.