It's time to spend some MONEY and instead of buying another gun I'm putting money into what known already. First up is my m&p .40, as we know the trigger SUCKS! I hate the long travel long reset and the safety built into it. I don't shoot competition or anything its used for home defense and at the range on occssion. So I'm not sure how far I want to go...just buy a APEX trigger or get the complete kit with sear? What's the advantage to go full kit compared to just the trigger? Also I think I'd prefer a curved trigger but APEX sells a lot of straight ones how come?

I put a flat trigger with forward set sear kit in my 5" Pro and its my favorite pistol. I wouldn't hesitate to recommend it, however I do feel the trigger is too light for carry. Its a great gun for an afternoon shoot on the farm.
I also have the apex blue line trigger carry kit in my Shield 9mm and its my second favorite trigger. Others here have put in just the sear (1-dot for your FS 40) and been very pleased. For me I wanted more than the sear because I don't like the hinged trigger. The kit comes with the Ultimate Striker Block (USB), sear, springs and the alum trigger.
I like the curved trigger alot. IF I bought a FS (4.25 in) M&P tomorrow, I'd put in a duty carry kit and a curved trigger. I wouldn't do just a sear.
But for my Pro, I wouldn't change a thing. Love the flat trigger in that....

Can you please provide the part # for this kit?

100-079
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What if I just ended up putting the apex trigger by itself? I'm not a professional shooter or anything I just dislike the two piece trigger. Other than that im not all involved with travel and reset etc

Just the trigger would only reduce pre-travel and over-travel by 20%. They have a polymer one for $40.
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I get what you're saying about the hinged trigger, but I wouldn't do just a trigger. I'd install a sear also. Makes a big difference.
100-074
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For me, I'd do an aluminum trigger and for the cost of the trigger alone I think its a better value to buy the kit. Besides, Apex engineered the duty kit to provide a superb end product, I think its more than the sum of its parts.

I have the thumb safety so adding this stuff will not cause a problem correct

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Would this kit be better or no?

Thumb safety won't effect the Apex function, it will work same as with stock trigger.
The forward set sear will significantly reduce pre-travel and be much lighter. Its what is considered a competition trigger. Its whatI installed inmy Pro 9.
Be aware, a trigger bar loop adjustment is normally required with the FSS. I did my kit installation and adjusted my trigger bar loop. Wasn't hard to do.
With a duty kit or the 1 dot sear you won't have to adjust your trigger bar loop.

The best kit for home defense or carry is the apex duty carry kit, I have it on my 9c and absolutely love it, my trigger was heavy and gritty like yours. After installing the kit along with the polymer trigger it improved a ton, it is now crisp and clean, nice reset, min overtravel, and trigger pull is now at 5.5lb.

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The FSS kit with the flat aluminum trigger is also nice, but IMO too light for a HD/Carry gun, I have one on my FS9 used mainly as a range gun.

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M&P 9, Shield9.

Installed the Apex duty/carry trigger kit but replaced the flat trigger with my hinged trigger. Couldn't be happier.

I wouldn't spend any money on it. I would buy a gun with a good trigger like a 1911.

Yep...my suggestion too. Sell it and buy something in 10mm or .45ACP made of metal.

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USS Brewton FF1086
SWCA#3597

Check out this demonstration of the Apex...
A MUST-HAVE UPGRADE FOR S&W M&P (APEX TACTICAL TRIGGER) - YouTube

I've got the Apex flat faced trigger (complete set) in an M&P .40 Pro CORE. I also have a standard M&P .40 (bought used) with the Apex curved trigger set.

With the grip size I like on it, I like the reach to the trigger better on the curved trigger.

Trigger pull can be changed based on which of the 3 springs you use: original OEM is lightest, then silver, then green is heaviest. Trigger pull is supposed to be the similar/same between the flat faced and curved triggers. But I see some variation.

For the Pro CORE, I've got the original OEM spring in it. It is light (checked at just under 4 #) but I don't find it too light for my use.

For the standard M&P with the OEM spring, I found the trigger pull way too light. Do not have a trigger pull scale but it must be 3 # or less. So I've got the silver spring in this one and it was over 4# when I got it checked.

The green spring in conjunction with the APEX trigger is supposed to give you over 5# pull.

Overall, I like the flat faced trigger in my Pro CORE best based on the the pull and how smooth it is. Also had the trigger reset bar installed so it has a noticeable reset.

The S&W OEM .357 SIG barrel has been a nice addition for my Pro CORE .40. Got it on sale from Midway, for < $ 100 I seem to recall. You might consider that if you are looking for other upgrade/addition options.

I am planning to get the Apex polymer trigger, and do the "burwell" trigger job myself
for a new M&P40C that I bought this week

I have done the Burwell job on a Shield as well as a M&P45C

I was very happy with the results....... Anyone can do it

I would like to get a non hinged trigger though