I have (2) 16 inch rifles, and an sbr lower, with a 10.5, and (3) 12.5 inch uppers.
I have 3 M4s, 2 on the 16 inchers, one on a 12.5, the rest have the T1.
You cant go wrong with either, but if I could only take one, I'd go with the M4s due to the larger fov.

