Your thoughts please. I have a (so far) unmodified Bushmaster M4 mock with fixed handle upper. I desire a red-dot type sight, most likely without magnification because expected shooting distance will not normally exceed 150 yds. I am considering the Aimpoint M2 series and also the Trijicon Reflex sights. I like that the Trijicon does not require batteries but the Aimpoints seem to be VERY popular. Also... dot reticle or triangle? Which would you think better in my situation in the case of the Trijicon? Again, range not to exceed 150 yds., and as close as "in-your-face". Thanks for your comments.

Aimpoint ML2 in ARMS #22M68 ring on an ARMS #39A2 'goosenck' forward mount.

The Aimpoint is excellent.  With all the mounting hardware mentioned above, you will be into it $525+.

An Eotech is almost as good.  The optic is less than $300 and the forward mount is another $100.

The Trijicon Reflex is an abomination.