We have been lucky enough to have cruised all Radisson/Regent ships including "Song" to Alaska in 1992 (I think that was the year it was acquired by Radisson) and Explorer to the Antarctic in 1997 (that might have been A&K). Took our family (group of 10) on a Med trip on the Diamond (that was a very unconventional ship). A negative memory of our only cruise on Voyager (Baltic) - we were in room 700 - way forward - our butler complained every time he came to the room because of the long walk! Mariner and PG have been our favorites. Have recently switched to Oceania - more imaginative itineraries and greater value in our opinion.