I recently purchased an LMT MRP CQB and picked up the Troy rear flip and HK style front flip from Troy. When I went to zero my groups were good but aiming center mass I was hitting the head and to the right from 50 yds. I never could get to point of aim point of impact nearly raising to front as high as it would go. I put the detachable LMT sights that came with the rifle on was immediately spot on without making a single adjustment. I'm planning on getting an Aimpoint Comp M4 and would like to have a set of flip ups so does anyone have any suggestions. Mixing brands is no problem for me nor is the cost just looking for the best that will work. I already got my money back on the two Troy sights. Any imput is appreciated.

Its you.  I had the same problem but I worked them out.  If your forum is good than sight adjustments will make changes in POA POI

If you still have your Troy BUIS set you could have tried the LMT front sight with the Troy rear and see what is the change without the Troy front, then reverse it by using the Troy front and LMT rear so you could isolate which of the Troy sights might be out of spec.

Since you already got rid of your Troy set you could just use your LMT sights for now and get your Aimpoint M4 with a LaRue LT659 (Tall, 1.725") QD mount, it is a high mount which will make your iron sights be located lower 1/3 cowitness of your optic field of view.

I don't have a LMT MRP, mine is the Defender standard patrol model 16" M4 carbine with fixed front sight and I had used my different rear BUIS, LMT, KAC 300m folding, Troy folding, and Colt detachable carry handle, all spot on without any problems with zero at 50yd.

Three out of four of my carbines have Troy rear BUIS and it is my favorite brand, my only other carbine that don't have a Troy have a LMT fixed rear BUIS.

You might want to try another Troy rear sight later, maybe you had an installation error or you had a defective sight which is very rare but it happens to all manufacturers.