I wanted to build a fast quadcopter, but couldn't decide on the frame size, so I bought 3 Sky Hero OB1 frames - a 4", a 5" and a 6" frame.
They'll all run exactly the same components, except for the 4" frame which will have different motors.

This is the build list for the 4" frame, and is my first custom build quadcopter.

This was a challenging build in some aspects - there is very little room on a 4" frame and some of the soldering was very fiddly.
The Brain RE1 flight controller is really nice though (the autotune function is really cool), and the 32bit ESCs work well although there is no documentation on the web. I didn't flash them - they work straight out of the box.

I used the Spektrum receiver because I have a DX8. This receiver does not integrate well with the Brain RE1, and the telemetry options are unavailable so I have to rely on the OSD in the goggles to tell me what's happening.

Once the dRonin autotune process was completed then it became very stable and is heaps of fun to fly. It's very nimble and you can throw it around.

Photos and video to come soon.