Finaly got the Bitch tamed I think.
I gave up on flying with 3S batteries, too damn scary. Screws were coming loose an alarming rate even with thread lock and since a couple of foam blades let go and shot over my head, I've bottled out and gone back to 2S batteries but with the V200 motor which is much more relaxed flying. All the MG servos seem to be behaving themselves now, no more tail spinning.
Bought a Gens Ace 2S 1800mah 20C battery to try out today and I'm sure I'll be buying more of these. It just fits the tray lengh wise, and is the same width as the frame. Weight seems perfect, had it hovering hands off with no trim needed.
Was getting an average of about 7 to 8 minutes per flight with a bit left in the tank.