The problems K2 had the last couple years were pretty much with one model; the Enemy. For most people the Enemy would be a well made ski, but being a twin tip it gets major abuse. The first year it had the same graphics as the Stuntman, and was given to sponsored skiers. When it was mas produced for retail, it became black with white stars. This model had a bonding problem, and delamed reliably when skied hard. "Skied hard" meaning "hucking in the park". People that don't frequent parks, would have no problems with the Enemy. I think I was the only one of my group of friends that never delamed them. Of course, lots of people got over 100 days before they split, and then warrantied them for a brand new pair. So they actually ended up getting a pretty good deal. The new red Enemy seems to have solved this problem, and it remains my favorite all mountain everyday ski.
Other than that, K2 is a well made ski, and the ones from China seem just as solid as the US ones. Over the last several years I have had about ten pairs, and they have all held up nicely, even my black Enemys. Having worked evenings in a shop the last five seasons, I can say that no one company seems to be dramticaly better or worse in terms of ski durability.
Also worth noting: The factory finish on K2 and other skis has really improved over the last couple years, and they ski great out of the plastic. It used to be only Volkl could claim this. A nice trend.