I'm just building my first surround system. I have 4 M20's to start, I have hit a brick wall as far as center channel. I was hoping someone in the actual Polk forum could make it a bit easier. From other forums I have had people say go with the csia4, while others said no way to that because it is not the proper matching center. From the research I have done the best I can figure the "proper" matching is either the csi25 (older) or csr (newer). Any advice as to which would be better or it would not matter would be great, I have posted the link for the M20's so as not to confuse with the VM line...
In a perfect world I could fine someone who has the M20's and has used both, but alas ours is not a perfect world.