Hmm, I have mixed thoughts about them.
I suppose I like sixth-form in general; not having many lessons a week, not too much (if any) stress, and the other students there are alright.
But, coursework annoys me (I prefer exams), some of the teachers are, erm, *****, and around exam-time the workload can pile up and life becomes a bit tiresome and frustrating.
Overall though, they are pretty awesome. I work part-time and would much rather do a day in school than a day in work and having a part-time job does definatley make you appreciate school a bit more.