Looking to upgrade my back surround sound speakers

I am looking to upgrade both my back surround sound speakers as part of my 5.1 setup. I currently have Martin Logan Spire as my L/R and the Martin Logan Encore as my center channel. Any suggestions? Should I keep with the Martin Logan brand...do they make dipole/bipole/monopole speakers?

I have a beam about 10 inches behind the listening area and a wall in which I would mount the rears. I prefer not to dig into the wall and thus prefer mounted speakers.
I find the rear speakers are only marginally important. The small quantity of the sound directed to them (usually), seems to make them pretty insignificant in th broad scheme of things in 5.1 sound
I could very well be wrong on that, but I would not spend much on the rears.
The front, center ,and sub are the biggies IMO.
For a seamless presentation though, they should be the same brand/ series.
Thx Liz, I called ML and they recommended the Motion FX line for my application.
I'd go with ML, too. This will keep the voicing the same throughout the system, very important for a seamless flow from front to rear...

I would buy some used script i's. Those were fantastic srrounds and I love the design.
Dont get crazy on this idea of voicing for rears surrounds as noted its not exactly in your face sound. The content will be ambient, add space and depth with some affects mixed in. There is no need to be anal about them, as long as they are in the general ballpark you will be just fine.
I used B&W surrounds with Innersound Eros so I speak from almost exact experience. Also at that distance its questionable as to the need at all but I would do it if thats what you want, just place them high on wall so the dont call placement attention to themselves.
If you are only concerned with ambience, minimal surround speakers are OK. But there is quite a lot of music where the surround speakers are important... properly recorded antiphonal music in particular. I had to upgrade my surround speakers when I realized this.
I figured its more about home theater since it was posted here and yes music is a different animal but even so for the 6 and 7th channels I would challenge most anyone to know the difference of a carefully chosen non matched speaker over a matched one. If budget restrains you from doing a match, dont sweat it too much is all I suggest.
Chadnliz... Agreed. Same goes for 8th, 9th, 10th...etc.
In 10 yrs we are going to be listening to 50.8 systems lol
I just realized that the beam is only 7 inches wide and thus your typical back surround is ~10 inches. So I am now looking into Anthony Gallo speakers. Never really heard of them. What is your opionions?
They make a fine mini monitor and for what your doing it will work fine, just make sure you set correct crossovers as they have very limited low range output.
I'm confused, Pig2fever. Was your question related to side surrounds, 4 & 5 of a 5.1 setup or rear surrounds, 6 & 7 of 7.1 setup? If 4 & 5, and if multi-channel music is important, matching the voicing of the 5 speakers is important. Is there any music that invokes channels 6 & 7 or are those channels used for film effects? Although I've tried to be careful about matching the voicing of the 5 speakers, I'm thinking about in-walls for 6 & 7.

DB, these would be for speakers 4 and 5 for now....maybe would be adding 6 and 7 down the road. The reason is thinking about upgrading and getting away from the two rear sticks that I use now by wall mounting new speakers for a cleaner look.
Oh you called them back surrounds and that usually means the 6 and 7. Typically they are called center rears or surround backs.
For the 4th and 5th speaker you need to be a bit more careful in selection. Maybe the Gallo would do a fine job if its just for movies.