I want to take my mom and 2 kids next Dec. and I don't know which to choose. My kids will be 6 and 9 when we go. My mom will be 50. They have never cruised before. i don't want to spend more that $3000 for us all. I can get Disney for $2900 for and inside and $2600 for a D1 (balcony) on Rccl, i have yet to price the other 2. Can someone please tell me some good and bad about each line?