Based on my results with folded subs I'd forget the reflectors entirely. The second option saves a lot of work and a lot of wood and will likely sound just as good. I would drop the upper panel that leads to the mouth a bit to make the flare more uniform. In my experience the whole concept of flat reflectors as postulated by Huygens is flawed. Reflectors are only necessary above 200 Hz or so, and then to work properly they have to be round.