as prone as any other drive system. drive systems of all design are prone to wear and, eventually, failure. with that being said, I have had very good luck with my diamond drive on my m1000. only change the oil every 500 miles. have heard of some piling up on turbo m sleds and some 08's, so they aren't bullet proof. RMI gear drive is supposed to be the toughest, so I hear.
Also keep in mind that the dd system has been out for over 5 years now so age is starting to show some. And if you notice, the AC m series is the most common 2-stroke to be turboed and has been for the last 4 years.
