Thanks for the input guys! Appreciate it. Not quite sure what you mean by hoover things... you mean the protruding bits in front? Those are supposed to be kind of hover-pads, so the front doesn't touch the sand at all. I see your point about the treads (both of you), but they're not in fact for thrust (that's the jet at the back) as much as maybe for practicality (running over sand) which I thought would be better than wheels. I'll give it another think though. Oh, and I don't know what skid steers are either...