James,
You might want to consider trying the Guimbal Cabri G2 at Cotswold Helicopter Centre at Kemble.
The Cabri is the most modern training helicopter out there and a very stable aircraft to learn on.
I have done some flight training with Andy Moorhouse who is the Chief Flying Instructor at Cotswold Helicopter Centre.
He insists that all students are able to demonstrate an autorotation to the ground before they go solo for the first time.
We started practicing this when I had 15 hours and I felt much safer in the helicopter once I knew how to do it.