It really depends on your foot and preference. The mary jane is a 102 last so it is pretty wide, and it has very easy flex (like a four or something on their flex tongue system). The soul has (i believe) a 98 or 99 mm last so it will be better for girls with skinnier feet plus it has a 6 tongue (once again I think) so it has a more aggressive, higher level flex. But you can switch the tongues out so that wont matter much anyway.