It depends on your situation. I liked them, but I was a pathology resident who took step 3 way too late in residency. It was good for me, since clinical medicine was a distant memory. If you're in IM or FM, I'd think it's not necessary.
I am using Archer rapid CCS prep. I am benefiting from it. I do think they are a great help before UW given UW is not updated with timings and sequencing interactions. I only see about 25 CCS in this package. I see another option on their site that has 80 cases, do you have any experience with it? Are the cases repeated? Thank you in advance.