Surround speakers for Martin Logan CLS


I am planning on adding additional surround speakers to my Martin Logan CLS stereo pair of speakers.
Although I know that the best way should be to go with ML surrounds, I am considering to go with 7.1 setup and this would require additional wall mounted surrounds.
Do you have any suggestions for surrounds (preferably dipoles) that would match the timber of ML CLS. Another requirement is reproducible low frequency of these surrounds to be 45-50 Hz.
Thank you in advance for your input.
meta
in my humble opinion the cls is not a surround speaker it is the hub of a world class system. see my letter in tas on the top ten products of all time and the last page in tas paying homage to the cls.
I am sorry Gregadd that I did not make myself clear (English is my second language :-) - ML CLS are the main speakers in my system, they are driven with VAC Renaissance 70/70 amp...
I am trying to tie them to appropriate surrounds and one of the options for the surround speakers I describe above. If I will not find anything good enough, I will go with 5.1 surround setup and use ML Ascents as the surrounds.
I fully agree with your opinion regarding the CLS - this is the last speaker I will own :-)
dipoles don't make good surrounds. the whole point of of surround is the directional cues. try the magneplanars not terribly expensive, almost as fast the mlcls. some of the newer models are small. in fact I remember seeing an add for a complete surroud system by magneplanar. good luck!
I use the clsIIz with diffusors for my rear speakers and also for my mains. They are inexpensive enough now that perhaps you might consider a second pair. Just a thought.

http://steinman.mesls.org/stereo/DSCN1658.jpg