Facing a dilemma

With the current banner and the upcoming superfest im wondering whenever i should just spend all of my rolls (24 in total) for jiso/bazibastra so they can help with getting their UF + attempting to get hanzo since he looks cool (idk what he does i just think he looks cool) OR do i wait 3 more days to try to get better units (idk if there will be a guaranteed roll)