I've yet to find a new handgun that didn't work well straight out-of-the box. As for the used ones I've picked up over many years, I believe most, maybe all were unmodified, except perhaps the stocks and I would replace stocks with the correct ones.

Many shooters may not take the time to become accustomed to what they have in basic form by doing a considerable amount of shooting before "upgrading" and modifying. They often believe these alleged improvements will take the place of shooting skill. They don't.

Some improvements may truly be worthwhile, but usually only the very experienced handgunner can take advantage of such modifications. It might be best to develop good shooting skills first before making a decision to change anything. You may decide there's really no reason to do so.

There's some good stuff on YouTube, but much of it isn't.