We are familiar with the staff that moved over from Castle Hills Montessori and were very happy with the time we spent there (~3 years). The only reason we stopped going was due to moving to Frisco, and then we decided to hire a nanny since we had 3 kids with only 1 in school and it was more economical at the time.
Now we have 2 of the 3 kids going to school starting in the fall so plan on putting the smallest into Castle Montessori full time and just having a nanny for after school hours. I took a tour a month or two ago and the layout is very similar and everybody is very friendly. After looking at all the options I think we are going to put our youngest at Castle Montessori just because that is where we felt the most comfortable.