The Glock and QA triggers are significantly different. While the Glock trigger can be "staged" and has a short reset, the QA trigger has a consistant weight (can't be "staged") and must travel to the forward position to reset. The best description I have is as follows: the QA is the best DA-only trigger I have ever used (akin to a Para-Ordnance LDA, but with a shorter pull length), while the Glock (with the standard trigger connector) feels like a single action with a long, light take-up.
In terms of actual downrange performance, the QA is great out to 15 yards; after that (25 yds) you will have to work harder to hit the target. The Glock (again, with standard connector) is easier to shoot at distance. This is because the Glock trigger can be staged, and has a short reset. With the QA, you have a longer pull (relatively speaking) for each shot. If the Glock is equipped with a NY trigger, though, it's a draw at best.
I hope I don't get flamed for this observation, but I see the QA as being the gun the S&W Sigma should have been. The QA trigger is consistant and has a crisp break, and the manufacturing quality/workmanship/reliability is top shelf. Whats better (at least for law enforcement) is that the QA's trigger does not have to be pulled prior to disassembly (it has a button on the slide for that). The only downside to the QA, really, is the $100+ price difference compared to the Glock, and the non-standard accessory rail. Then again, you get what you pay for.....
