Small class for most subjects. Its easier to get the help you need if you need it, and it'd be a nice relax. I prefer to do my work in the evening anyway, especially in winter when theres nothing to do.
I've not been in either though, I had one small class (further maths, no surprise) which were smart, and then a lot of large classes which were mixed. I didn't really like the large classes, noone worked, meaning material was repeated. I know I said relax but doing the same pages out of a book twice over is a bit too far.