My hubby has always worn a dark suit. Part of your decision should be dependent on the cruise line. Carnival is one of the least expensive cruise lines and tuxedos are few and far between. Princess is a moderate price line, and no more than 25% of the men wear tuxes. the Wind Star line is pricier, but they have a dress code of "casual elegance" and don't have a formal night. We have never cruised on the high end, $12,000 per cruise lines, but suspect that tuxedos might be more popular on those.