I have tried them all,electric caravan scissor jack,small 1.5 tonn bottle jack,& trolley jack.THESE HAVE BEEN TRIED WITH A FLAT TYRE.
scissor jack does not lift from the closed position,even with the supplied jacking points. bottle jack will not fit under axle tube or axle plate & the trolley jack is to heavy to carry around when touring.the only proper answer is a Kojack replacing your car jack to save weight,or an Alko side lift jack.
some one mentioned a bottle jack under the chassis rail,this is not recommended by ALKO as it can deform the rail,(seen what damage can be caused by a breakdown serviceman using a jack under the chassis thanks very much)
Go for the new Kojack as the best option