Underground where I worked the one in the OP's photo was used primarily for drilling downwards, ie: in a underhand stope or sometimes for drilling horizontal holes for iron pegs in a very narrow drive or stope, in the first scenario weight, balance and a no fear of falling was needed, I would stand on the handle while the machine man would operate the machine, starting off a hole was down to pushy down muscle power, in the second scenario it was muscle power only and then some.
One with a built in air leg was always called a stoper, used for drilling vertical or near vertical holes in the back of stopes or for drilling holes in a box hole round.
One fitted to a jackleg was used mainly for drilling tunnel rounds, drilling benches in a shrinkage stope and drilling raise rounds....also occasionally used as a sub for a stoper when drilling box hole rounds (machine tied tight back to the jackleg)
Lozz.