The first thing that struck me when i took the mount from its package was just how little there is of it. As viewable in the product image, it really is a very small piece of plastic for such a valuable item as a GPS unit.
At first i was nervous of using it, but the weeks of trial its had so far have put my mind at rest. An example of excellent design and engineering my Dakota (mount also compatible with the Colorado and Oregon) clips straight on sitting on top of the mount with no lateral play or rattling. So firm is its grip it took me a worrying few minutes to work out that to remove the GPS, you just have to push the bottom of the mount downwards and slide the GPS back up, a process so easy you can do it with one hand.
I have it attached to a folding bike with small wheels and no shock absorbers, so it does take some fair pounding at times over potholes, cobbles and curbs with no complaints. The mount fixes with grip-ties which thankfully fit to any tube - my folder has very small tubes and i have experienced issues fitting bike lights to the frame but i had no such trouble here. The foot of the unit is square, with rounded tube indentations to fit snug. At about 3cm a side, I'd say that it would likely fit tight to square tubing larger than that, and smaller at an angle due to the indentations for round tubes.
Although costly for the small item it is, its design is sound it does its job well.