Had some 5.1d's on 440Fr hubs with supercomp spokes and alloy nipples on my Ransom.
They were built and went on in 2006, they did 2 summer seasons in Whistler (averaging 3 hours per day I reckon), trail riding, guiding and XC racing, also a winter on a Blizzard hardtail riding in the UK, North Van, Squamish etc.
Since then they've done another summer season of hard riding in Whistler by one of our guides who was probably riding 5+ hours a day all summer long.
He broke a few spokes and appart from replacing those, nothing else has been a problem. They are still straight, not dented and most folding Kenda tires are removeable by hand or 1 plastic lever at most.
I've dented a 4.2d (low pressures and crap bike control.. I rode over a sharp rock on teh virgin ride on my race bike) and put lots of dents in my DH bikes 6.1's.. none of which have gone out of true though.
The 5.1s have been superb.. pretty much fit and forget. The 6.1's have been somewhat frustrating but the wheels do take some abuse over a seasons Bike Park riding so its an issue that we have to accept.