In reply to SARS:
I'd say that of the Covent garden cluster, that Ellis Brigham probably has the best choice. they do have some ice, too. That said, you'll pay top dollar there. Slush and Rubble also worth a look. But, Urban Rock best overall (but further out from the cente).
I do rate an hour's settler on the ice wall at the beginning of the season though. Reasonable price if you bring all your own stuff too.