Seen a few of their older models crack, although the newer ones haven't really been around long enough to gauge their strength.
What Matt said - I still don't really get why people are happy to repeatedly spend loads of money cumulatively on Deng forks when they could just try out the Trialtech forks and have a stronger, better, longer-lasting fork. The initial expense is greater, but they'll outlast Deng forks with no problems.
Same here - people keep saying they're badly designed, but I'm running the mod disc hub on the back of my Lynx with no problems at all, and the 135mm TR hub on the back of my Echo. That's still pretty young so it's not really been tested, but yeah, I fail to see how they're badly designed at all. The main reason I got my rear TR disc hub was that the flange is spaced out more from the disc mount, so unlike the Rockman and Try-All hubs you don't have to mess around with your lacing to get it to clear the caliper, you can just lace it up as normal and not have any problems.