Their plant is in Holbrook, NY in the same plant that makes their sunrooms.
The window has a pocket

sill and uses Rehau extrusions. They are using the 'Conservaglass select' glass from their sunrooms in the windows as well.
Features include shadow grooved corners, interior glazing bead, quad weatherstripping, block and tackle balancers and PAL locks.
I've never seen one, so other than the big huge negative on it having a pocket sill, I have no opinion on the rest of the window.