I have done the 5 nt on the Enchantment and am doing it again. I am going for the 5th time on the Sovereign for 4 nts. I think there may be a tendancy towards a more party crowd, more singles, planty of kids. It really does depend on the time of year. For me it works better to do two 4 or 5 nts a year than one 7 nt.
It is only less expensive because it is shorter. The per diem can sometimes be more. I figure if I am paying less than $100 PP per day, it is worth it.