Glad to read that you are pleased with the ZM4 kit that you received from APEX!
The gun you built looks great!
I have been working with DSA for quite some time to get these complete rifle kits.
We already sold out of the mid-length kits with the 1/7 twist lite-weight barrels, but have added kits/uppers with chrome lined M4 barrel profiles 1/7 twist rate.
The next ones I have coming are similar and chrome lined, but are a straight barrel profile, without the reduced diameter in front of the sight.
That is the one I am going to use for my own build!
Thanks for taking the time to share your experience with building your AR!