It's painful (to a degree!). It's a lot of math, and the second year seems to be more chemistry than physics! LOL! But its great fun, and its really interesting. It's definitely not for the faint-hearted, unless you understand things the first time round/you have an amazing teacher who explains it in simple terms, then be prepared to really work hard and read around the subject.
WJEC is a bit of a pain as it has 90% of the formulas in the booklet, but doesnt tell you the other 10% (theyre not even in the specification!).