Well, the appetite thing could be due to temperature. My guys have a great appetite in a temperature range from 74-78*F. The addition of crickets (protein) to the diet will help speed up the growth. In my experiences, under these conditions, the babies will reach adult size in about 12-14 months (I'm not really sure how much weight per month). Do keep feeding them the MRP though, it is good for vitamins and such. And be sure to add calcium and vitamins to the crickets as it is very important for a growing gecko.