Does the Shield series have the interchangeable backstraps like the original M&P? Also, is the Performance series trigger that much better? Or would you go with Apex?

Can't answer the trigger question because mine is still stock.

There are no interchangeable backstraps. However there are a couple of options to make the grip more usable. Talon grips and I believe Hogue makes a Handall style grip.

I have a PC Shield and other regular MP's that i keep all stock. I have no need to modify anything on my MP's.
There is a noticeable difference in trigger feel for what i own but i havent shot a regular Shield to compare apples to apples. I did let a range officer who owns a regular Shield shoot my PC and he said he really liked my trigger. For what that is worth.

My shield has Hogue Beavertail grip, and apex duty carry kit. The grip is pretty solid, the trigger is crisp, clean, and lighter (5.8lb) compared how it came from factory. Haven't shot a PC shield so can't say much about it.

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M&P 9, Shield9.

My Shield triggers are good enough. And they got better with more shooting! The other stuff may be better, but I seriously doubt they would make my Shields shoot any better for me. So I spent the money for triggers and Performance Center guns for practice ammo. My Shields do what I need them to do, reliably and well. I like 'em. If they ain't broke, I ain't gonna spend any money and time on fixin' 'em, and maybe even make 'em worse or less reliable. Ain't sayin' that would happen, but I know what I have in my hand, and they will do nicely, Thank You!!

As they say, lots of lures will catch fish, maybe even more fish, but most of the stuff hanging on the store racks are intended to catch fishermen!!! Till I have a problem with my Shields, I'm just gonna shoot 'em and try to stay in good practice!

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So long ... Ken

Local store has both. I tried trigger on both (in store only).
The PC Shield has a better trigger in my opinion.
Have not tried a Shield with the Apex.

wyo-man

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Live free or die