NBME 18 vs NBME 21/22

Hey everyone, sorry if this has been asked before, but I'm taking Step 1 in 2 weeks and am planning on taking an NBME, UWSA2, and the free 120 before then.

I've currently taken NBME 15 and 20, UWSA1, and a couple of NBMEs offered by my school.

I know 18 has been a pretty good predictor, but would it be more beneficial to take 21/22 instead to get more exposure to newer questions?

Thanks!