Actually, whegs have a better rough surface climbing ability. A spiked wheel could at best climb a step of the same height as its radius (minus half the thickness of the spikes). Passively compliant whegs can climb something 150% of its radius (i.e. 3/4 of the diameter). Thats assuming you can get a grip. If the spikes couldnt lever the wheel, then you would have to rely on good ol fashioned friction. A round object such as a pebble would also prove less of a problem for a whegs than a wheel as the geometry of the object can pass inside the wheel (i.e. closer to the hub than 1 radius). So on a rounded object, the whegs would have better grip (due to the tangent of where it contacts). Wheels tend to be more efficient, however, a wheel slipping is burning up energy doing nothing. For rough terrain mobility, whegs are better than similarily sized wheels, spikes or not. So they should just wait until every single possible piece of technology has been developed before announcing it? Most things can be miniaturised given research and development. They've just shown the basics can be done. Other people can then add any other features. Did they say it can actually DO these things they're promising, or did they say it COULD do these things given more development?