I don't think there is one right answer (m)

If it doesn't work out, can you bring him back home? It sounds like a great place and the teachers sound terrific.

If you give him another 6 months at home, it may help his immune system and he'll probably be a bit more mature.

Either way, I think you'll end up in the same place a couple years from now.

Personally, I'd try it now because there is a chance that preschool would be exactly what he needs.

Sounds exciting. I remember those days. We sent DS to a parent participation nursery school and we had a blast. Three year olds are such a riot! (plus they're cute and funny too!)