How many hours did it take you?
Where did you get sources from?
Is it hard to get an A? / How do you get an A?
Yeah I recommend it!!! To be honest it took quite a long time (about an hour a week for a year maybe?) and I don't think my universities regarded it as very important, but it was interesting and helped me with lots of skills, so I guess it's a question of whether or not it's worth it for you. I got my sources online from Google Scholar and stuff. I got an A* but a lot of people at my school got lower grades when their projects were really good, so I'm not really sure how to get an A, but your teachers should be able to give you advice on it hopefully. Good luck!
(I also moved this thread over to the EPQ forum for you so you may get more responses in there )