The Comcast/Xfinity store in Atlanta on Ponce de Leon Avenue is offering a closeout on Sennheiser Urbanite XLs. $49.95, and they have quite a few in stock. I am not sure if they’re available at all Xfinity stores, but they might be. It could be worth checking out the next time you have to exchange your modem (or argue about your bill).
Kind of odd that a store like that would have that many sets available for sale – but it appears to be a pretty good deal if you’re looking for an extra set.