My wife and I went on Triumph in 2004 for our honeymoon. We went last year on the Valor. I enjoyed Valor much more. Valor is still a new ship and the decor is awesome. Plus Valor has like 23 or 24 bars.
I never been on either ship but I read Conde Nast Traveler magazine where they surveyed thousands of cruise passengers to rate their experience, of all the large ship from Carnival, only Valor made the list. Try it and let me know.
Never did the Triumph but just returned from the Valor. Definitely recommned the Valor, the nightlife was great. The disco club was great and played great music. The shows in the main theatre were awesome and at any given moment there was always live music all over the ship and the service in the bars and lounges wass great!