Having been on at least 9 cruises, 2 on Princess and 7 on Carnival, we opted to try out RCCL's IOTS for the itinerary. St. Maarten, St. Kitts, Labadee & San Juan. We have always enjoyed Carnival's party atmosphere, so we weren't sure a more subdued cruise line would suit us. We also weren't sure if we would find the large price increase between the two cruise lines worth it.
First I must say the ship is beautiful and check in was a breeze and we were onboard in no time, when we showed up to the port at 11 am. Our cabin, outside window stateroom was teeny compared to Carnival. That wouldn't have been such an issue had the bunk beds for our daughters (8 & 11) were not directly above our bed. We were not able to sit up comfortably in bed (my husband, not at all) when they bunks were down. We had to duck to get out of the bed to head to the bathroom in the middle of the night. Very strange layout. Bathroom storage was 1/2 that of a Carnival ship though we appreciated the closing shower doors in lieu of a curtain. Stateroom attendant very nice. Only shampoo offered in shower. No shower gel, free white strips, tooth paste as on Carnival.
Pools: LOVED the fresh water pool options....Carnival only does Salt. Many pools to choose from and a varying levels of depth for every age. We enjoyed the nightly movies (no popcorn though...Carnival wins this). We also missed watching the morning show on the big screen...RCCL has it on, but no sound.
Small, but size sufficient. Did not like the bunk bed lay out at all. Directly above our bed. Beds very comfortable.