My husband and I have been on many cruises, two of which were "quilting cruises". I enjoyed both of the, but the first one had four teachers, and we could only take one 3-hour class with one teacher. We did have evenings with the group and that was fun. The best cruise was one with Eleanor Burns, a 10-day cruise to New England to see the foliage and make a sunflower throw quilt! machines were provided and the room was available 24/7 - classes were held only when we were "at sea". We had a terrific time - there was plently of time to sightsee, and we were fortunate enough to find some quilt shops along the way. Eleanor included the husbands in several activities, as well. Most of the 25 participants got their quilt top completed, and several even got theirs quilted before the cruise ended.
Sorry this is so long, but I'm all for quilting cruises. Just make sure that you will have enough class time with the teacher to make it worthwhile.