Do any of the people who made the Zev Tech trigger have mechanical engineering degrees or millions of dollars to spend in R&D and testing to assure that the trigger functions as it was designed to?
Has your plastic Glock trigger cracked, deformed, or otherwise failed you in some way?
Why replace something that works that has millions of dollars worth of testing backing it from a firm that employs a number of mechanical engineers, among other types of engineers, with something that has a few people at most backing it?
If you wanted a target pistol or target trigger, why buy a Glock? The Zev Tech trigger costs 1/3 of what a Glock 17/19 costs. Does that tell you anything? Even if it works perfectly, it still won't make you a better shooter.