Overall I felt it was very restrictive on my education. My day consisted of a few required activities (copy down a few sentences by hand, do 5 addition problems, etc.) followed by doing whatever I wanted. My favorite one was putting together a cube out of these colored blocks, but there’s only so many times you can put that together. The rest of the day was basically spent in boredom as I’d exhausted all the activities that interested me. I spent a fair amount of time reading.
The restrictive part however was the complete lack of preparation on the part of the teachers to teach anything. I remember after doing addition for a while, I asked my teacher to teach me how to multiply. She said “no, that’s for third graders” and left. I basically pieced together that “two times three” meant 2+2+2 just from the way it sounded in English. What a way to shut down a child’s education.
I’m sure I had an abnormally bad experience, and my sample size isn’t enough to discredit the Montessori methodology as a whole. However, I was much happier and felt I learned a lot more from public school. My conclusion is thus that the quality of teachers is vastly more important than the methodology. If you have well-funded public schools in your area, I would definitely suggest them over a poorer private Montessori school.