Doesn't matter.
Oncidium was originally a 5* and given a 6* bridal variant for being first place.
Cactace is a 6* and given a 5* variant.
Camellia is a 5* for both versions.
Presumably our first-place winner will also get a 6* variant, but if you wanted an easier time at getting a rainbow downgraded to a 5*, you might want to vote for one to reach second/third place. Anything could go for the 2-4* girls.