I have no answer for that except to say if'n you believe what Taurus says about the X, it 'better' made....more attention to detail.
That being said, I shot my 856 with the factory trigger and did nothing to it except clean and lube under the plate. It was a heavy, but very predictable trigger. Close to 750 rounds without an issue.
Once I installed the Galloway kit, it only got better.
It's been around 800+ rounds since the install, honestly I stopped counting the rounds, and I've had no light strikes, or FTF. It just runs. No screws backing out, and I'm just waiting for JM or DSG appendix holster.