We did the four day and are rebooked on a seven day. I'm going to post playing devils advocate.
We rebooked on the afternoon of day two, the day before
Castaway Cay. We were having a great time. The kids were really enjoying the clubs. We were really enjoying the rum drinks....
On day three I was really questioning the seven day. My daughter had gotten overtired and crabby (turns out she had an ear infection). The cabin was feeling very small (might have something to do with sharing it with a cranky four year old). Dinner the night before had been "just ok." And my husband had been paged out of the show to the kids club.
We didn't spend much time on the Cay (wanted to keep Miss Crabby out of the sun - didn't need sunburn to make her worse), but the time we spent there was wonderful. Dinner that night was great and I was feeling good about the trip again.
The last day was our sea day and it rained. We had a great time, but there were moments that I wondered about the seven day again. I could feel the boat move, and while it wasn't unpleasant, it made me wonder what really rough seas would be like. And, while one rainy day out of four was perfectly tolerable, I wonder what five rainy days out of seven would do to my mood.
We are going on our seven and I'm looking forward to it. And I did LOVE our four. But not without reservations.....what if my kids get really ill instead of just crabby with an earache. Quarrentine would not be a fun way to spend your vacation.....what if it does rain five days out of seven? What if the seas are really choppy? Can I handle it? Will I go stir crazy in that little room with my children for seven days? Can I handle that long without a really good shower and soak (the showers left a lot to be desired - I might need the Rainforest Room just to compensate). Can I really pack to handle four people in that little room with formal wear and clothes for dinner and shorts and tops and shoes and suimsuits for SEVEN days (four was challenging enough!) There is something to be said for Barb and Tony's method of frequent short cruises.