Well I think so anyway.
So I got it last weekend and it had some FTE problems. I cleaned up the bolt carrier and bolt assemblies (sorta) and headed back to the range today. Well the problem continued.
Then I took the bolt/carrier assy. from my Armalite Carbine and used that in there. It worked flawlessly then. Closer examination of the bolt and extractor (with the helpful inputs of others) turned up a lot of "gunk" under the extractor. Cleaning didn't solve the problem. I put my Armalite bolt assy. into the Colt bolt carrier assy. and that combination worked fine also.
I guess I'll get a repair kit for the bolt assy. to change out the extractor, spring, pin & spring,,, and then see where that gets me.
Sure was happy to find out that the problem was only gonna cost $5-$20 to fix.
Well anyway, with the Armalite bolt in it I got to shoot several rounds. What a fun little gun.
The Wolff brand extra heavy extractor sping solved my M4 FTE issue. You may want to consider it if the problem resurfaces.