For KM K1, around 70% seat is reserved by its own PN student.
Refer to the web site of Education Bureau, KM has 113 K1 students on 2011 totally.
KV has 651 K1 students on 2011 totally.
Heard that both kindergartens have thousands of applicant also.
Compared with KM, KV has higher chance to get into K1 as no PN class at KV.
Surely, you have to consider which school is more suitable for your child also.