We normally do 7 day Caribbean cruise so this was our first cruise with overnight stays and we loved it. It's great to be able to sue the ship as a floating "all inclusive" hotel and take your time to explore the island and really get to experience things. If your used to the large ships it'll take a bit to adjust to the Summit, but once you do she is a great ship. The service was friendly, the food was generally excellent (for some reason Qsine and Tuscan Grille seemed better than on the Solstice class ships for some reason). We had the best service EVER in Qsine! The staterooms show their age a bit, but are clean and well kept.
Bermuda is a very cool place to visit, many different styles, architecture (from modern to old world caribbean) and geography for a such a small chain of islands. Due to the winds/currents, there are fewer beaches than you expect, but the ones that are there are pretty great! This was some of the best snorkeling we've done anywhere in the caribbean. Generally great weather, though a bit humid.
Overall I recommend Avoya Travel, Celebrity Cruises and Bermuda!
