Super Andy, I saw the trailer of your DVD on QC.us (one of my favorite online store ...) but did not know it 'was one of your productions, congratulations anyway. I think the idea of ??making a product for heavy configurations is a very good thing, because there is a big difference in a lot of points as for examples: the electrical wiring, the ESC, propellers, engines (and new engines 24 or 28 poles), personally, I find a pity that builders do not be addressed on the realization of Multirotor's ESC specially dedicated to a perfect true linear response curve... Luckily SimonK exists. .. If you want other more technical information I advise you to get in touch with my mentor here with the email address: (In MP) his name is Walter. Large configurations have no secrets for him and he has devoted his existence to do research in this area. I think you should send him a message from me explaining your future project and I think it will give you great advice. I have had the chance to know this person, my turn to introduce you ... ps : he speaks English perfectly, not like me... All the best For your DVD and future DVD. Marc.