Prediction: You will fall in love with Momo at the beginning of episode 6.5 (the OVA). Also, episode 7 and onwards have all the best Momo material.
I started out with Mikan as my favourite, but now it's Momo all the way.>>9678419
My love for Mikan and Manabi is more what a brother would feel, I think. I want Momo (or Mei if Momo's not available) for a waifu.