Having flown two Roo's with Gyros and attempting one flight on a roo without a gyro, I highly recommend the gyro on the nosewheel. I consider myself a conservative competant RC Turbine pilot, but once on preflight my gyro failed ground check and I took it out of the equation. Lined up on the runway, punched the throttle and that thing went left right left right and about 3 seconds later I was shutting the engine down as I was in the orange fence.

For $90.00 or so, very cheap insurance.