Cheers Tigerlily - I hadn't thought of the animals so much - more the uneven terrain and falling down badger holes or tripping over tree roots etc. I think I'll probably start by running over some openish fields that are close to the roads so if I feel really spooked I can 'escape' easily
I really want to do it, I've ordered one of those alpkit ones, they seem good value and if I get on ok I can always upgrade next Christmas - that's one pressie sorted already.