You probably mean the m15A2 tactical carbine, with the full stock? That’s the one I have. I don’t think anything M16 could be considered a carbine due to the large barrel. And anything with a shorter barrel is no longer an M16. but I could be wrong.
I much prefer the CA M4 variants to the TM, for a few reasons.
1. barrel assembly is one piece, so you don’t get the barrel wobble down the road
2. stock to stock the CA shoots a higher fps
3. full metal receiver
4. upgraded bushings right out of the box
5. all the nice arma-lite markings.
The only downside is the STAR mags don’t fit in the CA like they do in the TM. So instead of spending $40 on 10 mags you spend $20 a pop.
Do you want an M16 because you really like the M16? For Airsoft there is no real advantage to having the full size M16 as apposed to a carbine (m15a2 or m4).
I really wanted a G36, but what really swayed me to go with an M15 was the fact that all the guys I play with use M4’s or M16’s, and they all use the same mags. So when im in the field, and I run out of dog food, I just have to call up a team mate and borrow a mag.