I got out of quads for about 18 months and when I started researching last month I was floored by how much micros have improved and costs have come down. I decided I wanted to build a 3" screamer on 4s under 250g. I'm crappy at html and formatting so hopefully the pics are pretty descriptive. It's in reverse chronological order on purpose? Check it out!

Update I got the board oriented in betaflight and the tx/rx working but motor 2 doesn't spin. I disassembled and swapped motors and motor 2 still not spinning so I figure it's a faulty ESC (I confirmed all the motors spin up, but no motor spins on ESC 2). Sent an email to PiroFlip RC for a replacement, hopefully hear soon and I can get this bird in the sky!

UPDATE 2 I'm a big dummy and dropped a tiny spec of solder in one of the channels of the board on ESC 2. I pulled it off with copper mesh solder remover stuff and now it's spinning! I haven't gotten all the motors moving the correct direction yet (I'm going with reverse direction to minimize prop wash with the tiny frame) but once I do I'll update with some photos of betaflight settings and some DVR flight video!

UPDATE 3 It wasn't as fixed as it thought and the number 2 motor was still wonky. I got a new 4in1 ESC board and got it installed tonight, all motors spinning well now. I'll get some FPV video up this weekend.