I have installed three SquareD NQOD panelboards in the last two months. 200 amp single phase, 200 amp three phase, and 400 amp single phase. All of these are either top or bottom feed. The factory sets them up per customer specs but they are field convertible. In the commercial installations where I am using them, I prefer the main breaker on the bottom since most new commercial services here must be underground. I have also seen the center feed type (they were old), but I can't remember the brand.
