I took 4 A2s (French, English lit, history and sociology) and it was a lot of work, especially around coursework deadlines and exams, but definitely manageable if you make good use of frees to get homework out of the way. I ended up with AABC, but the B was only 4 marks off an A and I don't think I could have got an A anyway, at least not without resitting an AS module. The C was completely unexpected and probably arose from me totally misreading the questions and going off on a tangent. So I don't think my grades were affected by the workload.