Piltdown man, I think the answer to learning to fly an autogyro, if you already fly fixed wing, is to find an instructor who teaches on both. I got a quick brief on the differences before my first lesson and a demonstration, so as soon as i had the controls I felt fairly comfortable. The hardest part for me so far has been the takeoff, which involves getting the rotor up to speed with the pre-rotator before the takeoff roll. haven't really had to unlearn anything, but in some manoeuvres there is a slightly different way of getting the result required.
So, yes, I felt pretty much at home fairly quickly.
But i still have a lot to learn, I haven't yet flown in difficult conditions, and I've only done a bit under five hours.
The machine I'm flying is a tandem, open cockpit Magni, by the way. Rotax engine with a turbo.
You should try it, it's a great experience.