I am considering one of these 223 Bufferless pistols however the YouTube reviews are not good
They say parts are breaking or need changing often a you have to buy them through that company and they are not cheap. There is a lot of talk about a special bone shape pin that seems to be a problem.  Now the newer guns have a slap feature for charging the gun but there is no last round hold open just a plastic piece that fits over the top rail that holds the side charging handle back. Now after the reviews this doesn’t sound too good but dose anyone have one of these that cam give me some honest answers about how these function hold up and perform

FM changed the extractor pin design to eliminate the wasp waist that was breaking.  I don’t know anything about a slap feature. I added a folding cocking handle to mine. After initial charging I just use the bolt release. 11.25” adjustable gas upper I bought from AIM in the spring. Have maybe a 150 rounds through it of 55 FMJ with no issues suppressed or unsuppressed. Getting around 2 MOA with my reloads and magnifier on 2 MOA red dot. Recoil is light, nested action springs are stiff at first.   I think the design is good for compact carry, bag gun, vehicle use, etc.  I have no idea about long term durability or holding up to abuse but the design, build materials and quality of implementation seems very good.

I'm a 07 FFL (Manufacturer).  I cannot say it any better or any louder than STAY AWAY FROM FM PRODUCTS!!!!   Problems, problems and more problems!  Junk parts.  Customer service?  Don't make me laugh.  Thier idea of a warranty is to send out "how to" videos via email and fix the problem yourself.  If you doubt my word, send an email to Rudy @ Macon and ask his opinion.

I watched some videos and that is kind of what they were saying also. I really wanted to try a Bufferless but after watching FM own videos. I realized. I don’t need one of these they are trying to make an HK. I have one of these. What am I thinking!!  Thanks for helping me save money but most of all saving aggravation

I bought an FM bufferless 11.5" kit from Optics Planet (OP) back in December or so.  It was shortly before they started offering a .300 blk version.  OP was kind enough to accidentally send the same shipment out twice and only charge me once...  lucky me -- a spare upper to play with.

I spent the $7.50 for a spare recoil spring assembly (2 springs + guide rod) from OP around the same time and haven't touched them.  Each upper came with a pair of extra extractor pins.  Haven't needed those yet either.

I converted one to a 9" .300 blk (Faxon), and have had no issues with the upper thus far.  I run it suppressed with an standard low-profile gas block.  I only have about 200 rounds through it.

I converted the other one to a 12" .350 Legend.  Again, a non-adjustable gas block.  That one has fewer rounds through it.

I've only had a couple of complaints thus far.  I recall their choice of screw head for the handguard crossbolts really pissed me off, and as well as how their handguards ride so close to the uppers that truing the upper or over tightening the barrel nut, even just slightly, alters the vertical alignment of the handguard/barrel.  I didn't like their barrel nut, but that's because it is proprietary and requires modification to work with most other barrels.

I never fired them with their original barrels, so my experience is not reflective of an off-the-shelf purchase.  I bought the upper knowing I was using it for a project, so, take that into consideration with reactions.