I have just sat 8 out of the 14 exams and failed two.
I would say that they are difficult but not impossible.
The fact I failed any was most likely down to the volume of stuff I pushed into my tiny brain which in turn obviously pushed more out that I would of hoped, it also did not help working full time, but on a positive side I still bagged six and the other two will also be in the bag soon.
If you have the time, commitment & desire these exams can be achieved.
Good Luck
YYZ