If you mean the xp, it will be for whatever class you're on. If you mean the equipment rewards, the rewards for quests are dependant on the quest proper, and some may be gladiator gear, and some won't. It should be noted that until the questlines merge at about 15, the equipment rewards are tailored for the classes in that region: For Ul'dah it would be gladiator, pugilist, and thaumaturge.