DJI 550 Build.

[andys]

Finally picked up my DJI 550 kit from the post office depot. The arms are certainly much more rigid than the HobbyKing Clones.

Started the long process of assembling / soldering it.

This is the Spec.

DJI 550 Frame
SunnySky 2212 980KV motors
RC Timer 10x4.5 carbon Props
3S - 4000mah lipo's (or 2x2650 3S run in parallel)
Afro 30 amp (Simon K) esc's
DJI Naza V2 & GPS
Aeroxcraft Landing gear
Tarot (or possibly Zenmuse) brushless Gimbal + GoPro 3
LED lights along arms
(Lights and Gimbal running from a separate 500 mah 3S battery to isolate it from the Naza)
Turnigy 9X radio & Turnigy Receiver


Thing is - after all I have read - i'm still unsure of what to do re the radio / props and lipo's?

1st - Turnigy 9X and standard receiver. There is no failsafe, which scares the hell out of me. I have set the Naza up so I can force a failsafe on the Gear Switch, but this doesn't help me if I fly out of range or loose signal. Initial thought was to buy a 9XR and FrSky RX/TX as I want to keep the 9X and receivers to fly my KK2 Quads. But - then there's the cost + wait from Hong Kong The new FrSky Taranis looks nice but no-one has them in stock.

2nd - The Lipo & Props. Should I run 3S or 4S - and what combo of props gives the best flight time? I have a few 3S lipo's so that's what I was going to use as 4S on my other Quads is plain silly / wants to rip the arms off!

Any info from the 550 guys appreciated - also any build tips as i'm in no rush to get this into the sky, I want to be sure it will come back home should I have any problems with it!