Since we are clarifying, my DD's play based preschool also has beads and stickers, wooden toys, coloring, crafts etc. and not Barbie dolls and race cars. But it also has dress up areas, workbenches with real tools, a play store with cash register and money. They grow gardens and raise butterflies and baby chicks. They take nature walks and visit horse farms. It is child based and child led learning. The difference I found was that at a play based school, the children are not taught the "proper" way to play ("work") with those toys. It is not a sequence. If my daughter wants to take the pieces of a puzzle and build a robot with them instead that is encouraged. If a group of children want to get together and lead a parade of instruments, great, the more the merrier! When we toured the Montessori school, we were told that no more than 2 children could do an activity at any given time and only on the designated mat. It was quiet as a library in that school. At the Montessori school the children were taught to self serve snack whever they wanted and clean up after themselves, not distubing others. At my DD's preschool, snack is social time. I feel that she can learn to be self sufficient at home, but I am not able to teach her to socialize with peers, she has to learn that through experience.
Our decision not to choose Montessori was not financial (our DD's school is also private) or out of ignorance of child development. It just wasn't what we wanted for our child. As some other pps have said, it is great for some kids, not others.