Yes, I went to a Montessori school through 6th grade (now 25 years old). I have mixed feelings about the experience. I agree that it did well to set my up academically. I ended up going to middle/high schools that were relatively average academically, so I was pretty strong in all subjects in comparison to my peers. Ultimately I went to a very prestigious college and now work in a wonderful finance job I love. Howeve…
While I believe your experience to be entirely legitimate, what you are describing is the norm throughout most of Europe and I can assure you that most of us are socially adjusted (or at least somewhat socially adjusted).