I installed my apex kit. I spent $102.00 with shipping. Is it worth it? Not sure? I test each component as I installed them. With the USB, hard sear installed, the trigger was lighter but a little mushy. I installed the sear spring and that felt the best out of each of these combination's, but still a bit of a mushy trigger. With the trigger return spring it's basically the same but with a heavier pull. All in all the kit is not going to make your M&P feel like a good 1911 trigger, but it does lesson the poundage a little. If you leave off the trigger return spring then it does lighten it a bit more.

The kit was easy to install EXCEPT the sear return spring. If you're not careful you will lose your spring plunger.

102.00 dollars might be to expensive for this kit, but that's up to you.

I bought the sear back when they were $30 and the USB when they were $25 so I don't have as much invested as you. I used the stock springs.

What I found was that the Apex parts really shine when you're pushing them fast. After installing the parts I shot an IDPA match that had a lot of moving targets and disappearing targets. The trigger speed was amazing. Big difference from the stock parts.

Yeah I might use my stock trigger return spring

I recently installed the Apex DCAEK ($90 shipped) and my experience was a good bit different. I also reassembled and tested after installing each step and found all to be an improvement over the stock parts. My trigger turned out to be far better than I wold have thought possible for a striker-fired polymer gun. Trigger pull weight strikes a nice balance between being heavy enough to be considered a safe and responsible weight for CCW and being light enough that it has no negative impact on accuracy when target shooting. Pre-travel is very smooth, the break is crisp and consistent, over-travel has been practically eliminated, and the reset is short and very tactile. The Apex DCAEK turned out to be a wholesale improvement over the stock trigger.

True - it's no tuned 1911 trigger but then the M&P is a very different pistol than a 1911. Trigger preferences can be quite different from one shooter to another. With that in mind I can see where the Apex kit may not appeal to everyone. I assume there are variables (tolerances) from one M&P to another that will affect how the kit affects every aspect of the the triggers function and how it will be perceived by the shooter. I just thought I'd post another perspective / outcome. Mine is no more or less valid than the OP's observations. Different pistols and different shooters.

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M&P15T M&P9 M&P9c SW1911 4506

The Apex kit makes a huge improvememt but its never going to match a well tuned 1911 trigger. Apples to oranges...

The Apex kit, just transformed my 45c from a gritty, mushy, trigger at 6-7lbs to a short, crisp break at 4 lbs.

How this translates to actual use for me: I now ENJOY shooting the M&P 45c and not letting it languish in the bottom of the safe. It's also a comfortable carry gun.