Whatever works for you! I think consistency would be good, versus two different places.
Around here 2 days (9 to 1) is about $150 a MONTH. I know that's not a full-day, but still. I personally have found daycare preschools to be less than ideal for the child but very expensive. The staff turnover is high. Their wages are very low. Their hours are long and they are only human. The brochures are lovely but when I'd observe, it was more like keeping kids in a room, calling it preschool and not really doing a whole lot.
Of course, it depends on the school. 2 or 3 hours programs that specialize in preschool tend to be really good, but again, if the hours don't work then that's not for you. Most of my friends had their children with a home daycare provider, who drove the child to a preschool 2 or 3 days a week (a 2 hour class).