I've always thought that OB was interesting; I think Ryan's tried it and isn't happy with the overall performance. I have drawings of my basic Nimbus OB, with an added 15" on top. Because of the huge size and cost (and lack of enthusiasm from others) I ended up abandoning the idea. As a side note, because of Vapors Meteorological theme, I was going to call my giant OB design "Sharknado". Because it was sooo over the top.