I think it's up to the individual. Me, I changed out my trigger and ground some areas that were contributing to "gritty" trigger pull. Now it's not gritty, and has a very clean break. I've removed the bluing from my barrel, ejector, takedown lever, and slide release. I've changed out my grip, grip tool magazine plates, and mag release with stippled ones. I don't think modification is a bad idea. I don't even think having a light trigger pull is a bad idea. If you're cutting springs, etc, sure, have a professional do it, but if you're just swapping parts, there is no need to pay for that to be done. All of this is just IMHO.

I think any legal issues you have would boil down to whether or not it was a justified shooting. Not how easy it is to pull the trigger. As much as the prosecuting attorney would like to spin it, that's what it would be about.

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M&P40c/15-22/SD9VE/Mossy500