I learned to shoot with a M14.
Loved it. I hit the pop up targets from 25 to 300 ydr (or it might have been meters) every time..seldom missed. It is great to have total confidence in your weapon.
I saw the first M16s arrive in our area and my first thought when I saw one was "Mattel". The also had considerable trouble in their early day and one of the reasons was a GAO swap to a cheaper powder that produced the same ballistics. It did that ok, but it was very dirty and the rifle was not designed for that. An example of the Bean Counters costing soldiers lives.
Was never issued an M16 and was glad.
Later, back in the real world, I learned more about the M16/AR15 and ended up getting a NM AR15. By far the most accurate rifle I've owned...but then I didn't have many rifles that should have been accurate. In my hands it out shot my NM M1A...but I fault me, not the M1A. A Marine gunny who happened to be at the range with a squad of recruits admired it and I offered to let him shoot it. What a humbling experience. Standing, he was making 2" groups at 100yds..in the center of the target. Honestly, I could not help but think that the right thing to do would be to give it to him.
Any way, I learned that in any kind of fighting rifle, a synthetic stock is better. Maintains accuracy better and requires less maintenance.
Also, a detachable magazine (that works) is better. Allows quicker access to a large supply of ammo.
If this stock is well done, it offers both those advantages to the Mosin.
So, if the rifle is going to be viewed as a Fighter rather than a Queen, it is the way to go.