Best in-wall speakers for rear channel?

Given a difficult room setup, I may install a pair of rear speakers in the ceiling. Any suggestions on what would pair well with Magnepan MMG fronts and an MMG-C center (Rotel receiver, amp).

I've been considering these 8" kevlar 2-way, angled speakers from Monoprice:
I have Niles HD-8's in my ceiling for the rears. I am not sure what model they have been replaced by, but they have been fine. They were about $599 retail when new. I have Maggie 3.6R's up front.

I have found that the rears fire so seldom that it doesn't make a huge difference in movies what the rears are, if you want them at all.
I helped a freind do his HT install and we used the Linn Sekrets with very good results. But there are many new options out there. I would really look at what is the closest voice match. And if at all possible go with magnepans that can be wall mounted or placed in a corner.
The voice matching is especially noticable on DTS and the new BluRay discs.
I am a dealer but 2 come to miod but I only sell 1 of them.

For their tone and wide staging I like and sell the Energy Di-pole in ceiling.

I don't sell but would also be a good tonal match is the Martin Logan in-ceiling speakers. They are a little brighter but your ear has some roll off from behind.