I cannot attest to the durability or break in period of these shoes as I returned them as soon as possible.
The rubber is far from sticky: as hard as I tried I could not stick to any angle. They seemed quite uncomfortable out of the box due to one of the lasts being slanted down and in. The sizing is also quite off compared to any other climbing footwear. I usually wear a 10.5 or an 11, so I ordered both of these sizes. Neither of them were anywhere close to fitting. I generally climb in 9.5 pre-downsized shoes, so I am accustomed to a tight fit but honestly, I swam in these and there is no way they would have performed satisfactorily while I scrambled and buildered. Lets face it, no matter how nice a shoe is, it isn't nice if it doesn't fit. I would like to give these shoes a second chance, but only under the stipulation that I got them for free. Sorry Adidas, but you missed the mark on this one.