TauLabs S2.0 CC3D Upgrade Version OP TL Dual Firmware Flight Control for DIY RC FPV Quadcoptor Multicopter Item NO.: F16821

Four stars for cheap if you don't mind fixing it. Three purchased at different times all had these fixable issues (if you can solder). They work well (all sensors including baro). I did get one lately that had a large mag bias, but works OK after calibration.
- You must carefully carve away a solder blob on the tiny tiny RF connector with a jeweler's loupe and modelling knife (not a soldering iron) if you want to use telemetry
- You must solder a power jumper (even though it looks like it is already jumpered) for the receiver power. Just solder a blob of solder over the jumper (actually a 10k resistor) that is there works fine. Tiny thing on back side of board top left between 5.0V and Bridge
- They replaced the RF telemetry LPF with a jumper to save cost. Don't worry about this. It works fine.
- This board is supported by firmwares from TauLabs, dRonin, LibrePilot, etc.