Like everyone else has mentioned, be aware of the tiny 1/2" flange included with this concession window. For an 8' x 4' window you need to be pretty precise with your rough opening for the flange to hit the structural material behind it (in my case, wood studs). I made my opening just shy of 3/8" wider and it was still a bit too much... I'd suggest a 48-1/4" x 96-1/4" rough opening for this window, no larger. The directions suggest for an 1" additional, which would leave you with a window that pops right through the RO. Otherwise, the quality seems good so far and it installed easily. We'll see how it does over a few seasons at the market.
Wayne 
