I liked First Class a lot, DOFP literally sent me to sleep in the last third after a strong start, not holding out high hopes for this.
Heh, funnily enough I thought First Class was awful, but Future Past was entertaining enough.
I never read comics so I just watch them as films without getting hung up on what the characters are /supposed/ to be like, however.
So from my perspective of comic book ignorance, First Class was literally awful, but Future Past was passable. And certainly more exciting.