First of all, anyone who has actually finished DIT will know that they don't just read FA. They connect things from different areas of FA together and really highlight the "must know" information. And they will explain stuff in FA as well.
I wrote down stuff from DIT into FA. Not sure how helpful it was because the amount of information in FA is already overwhelming. Also, I thought the primers were useless, but I really liked part 2 of the course. Quite honestly, at the end of the day, if you can even learn the information in FA, that itself is impressive.
I never did the adding uworld informatino to FA. I thought it would be too time consuming a process to find the relevant FA page and writing stuff down. Instead I used to just make anki cards for uworld information separately.