We were on our first B2B covering both the initial 3 day maiden voyage and subsequent 7 day Eastern Caribbean.
Embarkation: There were two parts to this process, at the airport and the pier. Both had some problems.
Airport: Meeting the Princess reps was standard but the wait for a transfer bus was tedious. On other cruises our wait for a bus was never more than 30 minutes tops. This one was closer to an hour and was complicated by the fact that there was another Princess ship (Caribbean) in port and there were separate buses for both unlike other times when all passengers were taken and care was made to ensure the luggage was properly separated. Also it seemed the bus drivers had little clue what they were doing and only added to the confusion.
A standard balcony room. Main space is adequate for two. Balcony is smaller that usual but not unacceptable. Best thing was in the bathroom that had a larger shower than other ships. Still not huge, but you don't bang your elbows.