My fiance previously had good luck buying a suit here, they even took his old one that no longer fit back for a discount on his new suit.
Given that and the deal we got at a bridal fair, we ended up choosing Mensusa for our wedding tuxes. While somewhat disappointed that they didn't have the tuxes in-store to try on and look at, they did let us try on similar suit coats.
They were quite patient while we mulled over vests, and gave their opinons but without being pushy.
It would have been nice to see the ties that go with the vests, but otherwise a pleasant experience.