Seeing that we have totally screwed up your thread here Kev, I must tell you guys that I flew my 450 yesterday, and made some observations. I did notice my tail doing some things, nothing major, but it got me thinking back to how the heli behaved on V3.1. I could not fault 3.1, so decided tonight to revert to V3.1.
Now I have to redo the whole DIR setup again. I can't remember how to, but luckily Tony's videos are coming to the rescue.
Did V4.0 work for me? Yes it did. After spending some time really flying the 3GX I realised that I preferred the handling it had on V3.1. Something did not feel quite right with V4.0, but I could not lay my finger on it. I will wait and see what V4.1 has to offer.