With the M&P Sport 2, in my opinion, you don’t “need” any upgrades because it’s a quality rifle and serviceable as is. That said, if you’ve got money burning a hole in your pocket and would like to make some upgrades I’d recommend some better flip up iron sights such as the excellent Troy battle sights. If you need an upgraded sighting system, I think a quality red dot sight that can co-witness with your iron sights is a good set up. I prefer Aimpoint red dots, they’re good quality. Depending on how you’re going to use your AR, I really like the the Tijicon ACOG system, great sight. A good 2 point sling is needed. I don’t like single point slings, and I don’t like getting hit in the balls with my rifle. Aside from that, an upgraded pistol grip is a nice thing, but certainly not needed.

As for the mil spec trigger, they are mil spec for a reason, they’re tough and reliable. My personal opinion is that an upgrade is not needed for a self defense AR. The stock trigger works very well, and a competent shooter should be able to get very good accuracy from it. There’s a lot of good after market AR trigger options if you’re so inclined. These triggers are great if you’re interested in squeezing out the best accuracy when paper punching, or building out a sniper or hunting AR. I personally think an upgraded stock is a better upgrade for a self defense or battle AR. Oh, and I don’t like flashlights on my rifles, but that’s just me.

I also believe that you’d be better off upgrading to a higher end AR than spending a bunch of money on a lot of upgraded parts. Just my take on things after going through it with several ARs.

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