Well looking at the comments I think I'll stick to the fields near by instead, they are small pebbles and although I don't mind scratching it up a bit and have some guards on the car I don't fancy snapping anything yet as haven't long got it running again. Thanks all :)
Silly question regarding driving on stones, so I used to take my Nitro car out on the red gra near my parents and it would slide around and be great fun however, it is no longer there. I have a building site near me that has a massive car park made up of loose pebbles which I was going to play...