my worry about my current carbon forks is I've had them for 2 years, and theres a reasonably largish scratch down the right leg and I've been using them in the wet quite a lot. As I understand it one of the fail scenarios is water weakening the internal weave over a scratch....
For someone like me whose fear of carbon breakage borders on outright paranoia, this statement is the equivalent of a ticking time bomb.
"I'd pull those forks off soonest", says Dan, who has lost some onetime pen pals to quadraplegia or death as a result of broken carbon forks. A few shops of my acquaintance keep their customers' retired/cracked carbon for me to view. It sure doesn't take much to render the material unsafe. One fork I saw developed surface crazing in the clear-coat on one fork blade right under the zip-ties that secured the wireless computer sensor. Another had been fitted with temporary mudguards and grit had worked its way under the plastic brackets that were secured by rubber straps; the clear-coat was again too badly worn to protect the carbon from separation and the roving (weave) showed signs of flex. Future installs used a strip of electrical tape beneath the brackets and no damage resulted even after two winters' use. Another sad case occurred when a bike's seat tube was clamped a smidge too tightly on a car carrier. Broken seatposts seem to outnumber frames and forks, likely due to exceeding the torque specs when re-tightening after an adjustment.
As far as the 531c forks go, they "should" feel a bit more lively, and the added clearance for larger-section tires is a boon for light touring, especially so on poor roads. If you won't be using front panniers in your touring, it is pretty much all-upside with no down except cost.
All the best,
Dan. (...who thinks carbon is terrific..until it [sometimes, occasionally suddenly] is not)