I have never believed in modifying critical components of a pistol (sandpaper, dremel, etc), particularly a self-defense pistol. Numerous reasons for this, but one should be particularly mindful.

Also not a trigger snob, it is a bit of snake oil if you ask me, however, 400 rounds is a pistol in its infancy. Put rounds through it, dry-fire, allow it to smooth itself out-- it is not a race gun.

What is that statistic? 95% of self-defense shootings occur within 7 yards? Get shots on target, do not see the real world application of wanting to group a bad guy sub-MOA with a 9mm at 5 yards, that is one small hole assuming he isn't moving.

Going from a 1911 to a Shield is only going to upset you, you knew what it was when you bought it