I've been on some old Commodore Ship (don't remember the name now but it was very old). Recently I've been on the Carnival Sensation and the Paradise three times. I will be on the NCL Monarch of the Seas in August but was unable to get a HA cabin so we'll have to park the p-chair in the hallway overnight and run an extension cord into the cabin. We specifically picked a cabin at the end of a long hallway that ends with a wall and no through traffic. Hopefully we won't have a problem with staff. I've already notified them that I plan to plug in overnight and they said it shouldn't be a problem.