First, I will say that we are fans of Celebrity/Azamara and have booked them exclusively, except for one Holland America cruise, because of their non-smoking policy (no smoking in staterooms, on balconies and only in limited public spaces) and the more upscale experience. Past Celebrity cruises included: 12 night Mediterranean on Millenium concierge class (CC), 7 night Southern Caribbean on Summit and 12 night Baltic on Azamara Journey.
We've always found the service, staff, attention to detail and overall experience to be excellent. This was not the case with Century on the 4 night Western Caribbean cruise!
I realize that Century is the oldest Celebrity ship in the fleet, but we booked CC and still expected a Celebrity experience.
If you'r a non-smoker, don't select a cabin on deck 10 aft, port side (underneath the spa). The rooms and hallway get smoke through the ventilation system from the deck above.