Yes, in fact I have completed the ACA. I trained and completed by ACA exams whilst on the graduate scheme at PwC. The majority of large accounting/ professional services firms send you to a sort of college/ classroom environment where the teachers help prepare you specifically for each ACA exam. PwC currently sends their graduates to Kaplan, and they are extremely helpful.
I would say - try not to be intimidated by the ACA exams. Yes they are challenging - the ACA wouldn’t be worth having if they weren’t! - but if you put the right amount of work in and use the tools provided by your firm they are definitely do-able! With the exception of the Case Study (the final exam), if you work hard and practice continuously and stay organised you can pass them! Don’t underestimate the amount of work you need to put in! They usually give you homework/ practice to do every night, and it may seem excessive… IT’S NOT! Make sure you do it. Another bit of advice: really make sure you understand one concept before you move on to the next! Things get complicated quickly if haven’t grasped the basics.
Case Study is a little different - it requires a little more finessing, but as I say, the tools are there to help you and you will get through it!
I should ask - where are you doing the ACA exams? If you are doing them independently, have you considered a classroom environment for help?
I hope this helps! Good luck!