Not sure if it's relevant, but I've knocked my Nano off the table about 100 times now (because it's so small and light) and it's had no problems with that.
When I used the glass VHW, the cord was a constant issue. They made the cord extra long (to try to help with portability) and extra thick (for durability), but it ends up just unbalancing the unit and makes it easy to knock over. I love that vape though, and so I took those little velcro-backed clips that are sold to hold down speaker/pc wires, and harnessed most of the cord down. Cut down on the portability, but since then haven't got caught in the cord or knocked it over.