Compact ACOG's are primarily meant for carry handle mounting. They do sit low on the carry handle, so cheek weld shouldn't be an issue. Then again, for me, all collapsible stocks have a cheek weld issue.
You can purchase a picatinny mount for any Compact ACOG. The TA33-8 comes with one by default. The TA33-8 is the only compact ACOG with a chevron reticle and a BDC that goes out to 600m. It is calibrated for M855 out of an M4. So that would be the 62gr nato bullet out of a 14.5" barrel at about 2910fps depending on barrel, ammo lot, and atmospheric conditions.
A 16" barrel would be close enough. Certain heavy loads (68, 69, 75, 77gr) can be made to match the BDC of this ACOG with a slightly adjusted zero at 100 yards. It will definitely be close enough for "business" and absolutely within the accuracy capability of the platform.
Compacts are mostly geared toward being a good mix between speed and range. The lighted reticle and low magnification makes it easier to hit with, yet it does have some magnification and a reticle (better than irons) for engaging further out. It is not ideal for any kind of close-quarters work, but neither is ANY magnified optic out there. It makes short range (non close quarters) engagement much easier and allows for improved performance at medium range. They are very small and very light. So they do not burden your rifle with clutter and weight. That is a good thing, since it is suppose to be a carbine, not a 12lb behemoth. They also give you night time capability without switches or batteries or electronics. That vastly improves reliability and robustness. That makes it more dependable. Even in bright daylight at high noon, the lit reticle becomes super-bright, more so than any electronic reddot that I've ever seen (aimpoint or eotech) and makes it extremely easy to see the reticle vs. any background and to do so quickly upon cheekweld. This makes it faster.
Of all the reticles, I'd avoid the dot. Triangle at least gives you the point to use for a little more precision. Crosshair is nice. Best of all is the Chevron in my view, but it is a 3x. Don't know if you'd want a lower magnification model. They also vary in magnification, FOV and eye relief. This can be a concern depending on intended use.