driving stubbles on big arable land is good crack keeps dog fit , and fills the bag ,done it for 25 years , never on sown or crop just setaside and stubble even done it in daylite for the crack we let dogs out on feilds and they jog along beside vehicle ,get a rest inbetween feilds , dont drop them on qaurry unless ,need the game , takes a good bit of wind to last the nite when i was bang at it ,half saluki ,perfect ans some hard bitten collie types , but you had to keep them fit of they would blow up early doors ,