Before I made my skimmer purchase, I went down the same road.... you know, why do deltec and h&s use extruded acrylic when I can get euro reef with cast acrylic? I own plenty of products that are made of extruded acrylic and can tell you that at least from an aesthetic point of view, cast acrylic looks better.
Now that I have an h&s, I can tell you that whatever acrylic they are using, it is not the same grade as the typical extruded acrylic you see here in the U.S. The acrylic on the skimmer body does not have the striations you typically see on extruded acrylic. Additionally, it does not have the imperfections and blemishes you would typically associate with extruded acrylic. Since I've never seen any real specs on this kind of plastic (nor would I understand what the specs mean), I can't really speak the strength of this plastic. All I can say is that I have an abundance in faith in the experience of h&s (and deltec for that matter) and therefore trust their judgement in the quality of the plastic they have chosen to use.
The fact that other brands of needle wheel skimmers do not use re-inforcements in high stress area does not indicate that they have stronger materials. To me, it indicates that the other manufacturers have not evolved far enough along to do the things that the more mature and more experienced manufacturers are doing. I have plenty of examples of cast acrylic being damaged through the course of normal handling. Not reinforcing high stress areas is just plain foolish if you ask me. Perhaps you can only learn so much from reverse engineering???
With regards to the a200, there is a difference between two aquabees vs. a single eheim. My dirty math shows that with a single eheim, you get about 15 lpm of air injection. With two aquabees, you get 17 lpm. I would ask Brian for guidance to see which is more optimal for your set up. Personally, I think either will make you perfectly happy.
One thing I would also suggest is you call Brian and talk with him directly. His service is only second to none.
