Hi Roger,
The best choice is always the one that its more closer to the goal you intend to achieve. For example , If your goal would be hiking the Continental Divide or the appalachian trail, treadmill with a loaded backpack would be ideal.
If you would do a mountain with more technical movement , and more leg strength , stepping up a box, using a Jacobs ladder would be important .
Cheers ,
Pedro Carvalho