Oops, make that name S. Pseudocamellia, common name Japanese Stewartia.

I could tell you only from my experience that my S.koreana which is planted in SW exposure (6+ hours of afternoon sun) is always having fried tips on a leaves starting from mid-August despite being well watered.
However, I planted S.pseudocamellia in a friend's garden in an only available place where it is exposed 4 hours to the late day sun and it is doing great there.

funny, i had that same question once but my stewartia pseudocam. has been in full sun ( and 2' from the house!)for 12 yrs and surprisingly does fine.it is now the height of a 2 story house.with this drought it does have crisped leafedges this yr.
best,
mindy

Thanks Mindy and George. I knew that I would find folks actually growing this tree here on the New England forum who would share their experience.