I think it's definitely a mixed bag, and obviously difficulty is so subjective + on many exams there are choices of topics which may be easier or harder!
Out of the 2 exams I've done (both AQA), I found Sociology P1 quite straightforward with just a couple of complex bits in it, but nothing awful. Combined English P1 though, I came out the exam feeling much more deflated! It does have a choice of topics on it + for my school's topics there were some very obscure questions.