Just read your thread, thanks for all the detail!
I have that exact 3d printer, what settings are you using to make the prints that nice? I'm jealous
Also I use a 12v rechargeable battery pack for my vader, here is a link if you are interested in trying it. I have it powering 3 fans and a Rom/fx Revo and it's worked for me for over 3 hours, another vader did a test and the battery life for just the 3 fans was over 12 hours. Here is an amazon link https://www.amazon.com/gp/product/B007RQW5WG/ref=oh_aui_detailpage_o02_s01?ie=UTF8&psc=1