the conventional wisdom, with which i fully concur, is to match your center to your fronts as closely as possible so as to preserve a seamless presentation. ideally, you'd use a another ml summit as a center, or at least another ml with substantially similar drivers, impedance, etc. rears, which generally aren't as prominent in the surround mix, are less critical, so you should be fine with your vsteens.
matching center channel to mains/rears
I am getting a new HDTV, been out of home theatre for a long time. I need to pick up a center channel. My mains are Martin Logan Summitt's. I am looking to find an adequate center, as the "best" seems a tad pricey. Is there any loss in switching to a different brand of center, say going to a B&W? Also I'm using an old set of Vandersteen 2ci's for rears.