This is a build that I ultimately just wanted to play around with. A build that a youtuber named Skidoosh did inspired me to build this. Even though it was intended to just be a challenging build, it turned out to be one of if not the most fun quad I have. I've experimented with many different props on this from HQ 5x4.3x3 V2S, HQ 5.5x3.5x3, HQ 6x3x3, Gemfan 6042Rs, and the ones I found to work the best for me, the HQ Ethix K2 bi-blades. The 5.5x3.5x3 and 6x3x3s work well too but the bi-blades are the sweet spot for these motors. I imagine larger and slightly lower kv motor would work a lot better for 6" tri-blades. 

About the build:
The frame is on 10mm standoffs so it is way to short to use a traditional stack. The 3 20x20 stacks on this frame are utilized from front to back as: flight controller, esc, vtx. The vtx cables are ran under the ESC which has not caused too much noise for me. I taped a 1000uf 35v capacitor to the arm and ran some 18awg wire to the esc. The camera was BY FAR the most limiting factor of this build. Out of 3 different nano cameras, the only one that fit was a caddx EOS2. Possiby a runcam
racer nano would work but I'm not sure. I had to cut the camera mounts for the camera to clear the bottom plate. This proplem could easily be fixed by integrating a camera mount/canopy into the tpu gopro mount. The vtx antenna is just held straight and attached to the standoffs by two zipties and some heat shrink. For the receiver, two antennas are ran on zipties perpendicular to the left front arm. The rxs-r sits perfectly in between the esc and fc. I've been running 1300mah 6s lipos and the flight time has been decent. They do sag quite a bit on punch outs but it is super fast so I could cap the throttle at 80% and never care. Would definitely hold a 1500mah 6s no problem.

The only concern that I have about the frame being that low is that the battery is directly in the prop line. It may be smart to run 5" or 5.5" props for that reason.