We cruised concierge as a treat in September on a 3-night Dream. We booked a cat V but got a free automatic "pixie dust" upgrade to a Cat T 1BR. Beautiful suite! We enjoyed the concierge lounge. The concierge staff was great. Very entertaining. We also got a cabana, which we have had before as a non-concierge guest. Give it a try? Sure! A must? Not for us. We are on our 10th cruise in January, and will be platinum after that-- which means we will have the same early booking opportunity as concierge guests (unless it changes). If you have the means, go ahead and book it.