I'm going to get an AX100 projector and am trying to decide on the best screen material.

Conditions:

58" X 104" screen
Dedicated HT with some ambient light. There are no doors on the rear entrance of the theater so some incandescent light will leak in.
16' from projector to screen
Room is about 18' wide
4 main seats at 15'
2 seats at sides

I'm thinking about a dalite permwall high contrast cinemavision. I beleive this is a slight gray screen with 1.1 gain.

Any thoughts?

It's helpful if you want better contrast and blacks in the presence of ambient light. A negative gain gray screen is also helpful in the dark by increasing ANSI contrast in rooms with light colored walls and improving blacks.