I stick to NCL even though they do NOT give me a break on cabins for solo traveling. I like that they ask me if I want to eat with others or alone at meals. It means that if I am in the mood to socialize I can share a table and if not I get the waiter all to myself! It's nice not getting stuck at the same table with the same people for the whole cruise, especially if they aren't quite sociable. They also have multiple restaurant options. In general (having cruised on RCL and Carnival) I like NCL better - it's just more laid back, which is exactly what I need when I cruise. JMHO - of course.
Michelle