I did a sociology course back in the day, quite interesting, it is however, 'lighter' than say cultural studies, linguistics or philosophy. I'd say Sociology and Anthropology are probably on par in terms of their theoretical rigour while the others are quite intense in their argumentative needs.
If you've ever done post modernism, cultural studies is very much a continuation and extension of what you get taught in high school. In fact, its probably better as it actually contextualises and explains why and how it has come about. If you haven't done any post modernism before, then I wouldn't worry too much but do keep an open mind, the worst thing you can do with those subjects will be to go in with a pre-determined view of the world without possibility of broadening it, those people tend to have real difficulty as it challenges the very foundations of our perceived social 'realities' and assumptions based on the cultural and linguistic theories that arose post-WWII