I currently own a Shield 9mm and I am quite happy with it but thinking about another gun that can be used for range practice and a secondary home defense gun.
Options I am considering"

Full size M&P 9mm $500.00
Full Size M&P Core 9mm $670.00
Full Size M&P 9 Pro 5" $600.00

Any thought on price and difference between these 3 would be appreciated.

If you have no desire to put an optic on the gun then there is no reason to buy the Core, IMO. So I would say the 4.25" or the 5". I have a 9c (which is a 3.5" barrel), I also have a Steyr which is a 4" barrel. I am selling the Steyr and I bought a Pro with the $. I hear good things about them and I think I am really going to like it. Just my $.02 worth..

I would get a Pro 5" for a second gun based on the purposes you mentioned. The longer sight radius will help a little with accuracy.

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