So I've been wondering the same question, and I guess it comes down to how much of a scale nut you are. The foundry figures are generally both shorter* and slighter than the DMH ones. There are also apache (4 figures) made by Galloping Major, which I believe are about the same size as Artizan and the old Westind wind/Old glory Cowboy Wars range has 2 packs of Apache renegades (2 'characters' with mounted/dismounted variants per pack.) No idea on size - guessing closer to new Foundry/Artizan than Old Foundry
* A couple of the Copplestone apache seem to be about the same size as the Mike Owen Cowboys, but most aren't. No idea why though!