I tried a search as well. Found little information but zone as 10a. I suspect that is probably more like it. The problem could be that there are many species of Microsorum and some come from alpine areas. People misidentifying species could be quoting zones for different species than punctatum. I have this species but I'm in a higher zone.

I don't have this plant, but was really considering getting it, etc.

Okay, thanks trop.