I don't have personal experience with the Revelators to be able to make a worthy suggestion. I do prefer the appearance of the uncoated versions which don't have shiny cones.
The Salk Sound suggestion is sweet! I get the downside of the MTM versus the WTMW but the MTM looks more sleek and is significantly smaller. Plus, I think it would be easier for you to build/complete a MTM version. Jim Salk may even be able to create his SupercCharged Song Center for you with Revelators if you desired that.
Have you considered trying a cheap center channel alternative to see, in your setup, if the driver compliment matters all that much?
I am open to idea, any input you can provide...there are some really nice cheap centers and i dont know