This first picture is the master model which is why it's in a slightly darker grey. The model shown on it's base is a 15mm dollie to help show how it compares to 15mm scale miniatures.
It also works very well with 10mm figures like Drop Zone Commander. Both HO and N-Scale terrain works well with them, although I prefer the N-Scale as the mecha appear larger and its also less expensive.
Some Scale shots shown next to a CBT Warhammer model
& Reaper CAV model.
Shown next to a Drop Zone Commander card stock building.