Yes, they’re light bike 35mm rims, built using conventional J-bend spokes and hubs (either Hope pro2 or DT Swiss 350s). My experience of them has been nothing but positive really. I have two sets, one that is about 15 months old on my sultan and the 2nd Set has been on the ‘Orse since about Easter this year. They do get marked on rocks quite easily, but no more than Stans aluminium rims IMO.
My reasons for purchasing were based on the desire to get a wider rim for better tyre profile and volume without paying the price of either extra weight or increased flexibility of wider alu rims. The internal width of the LB’s is 7mm more than my old alu rims for the same weight. They’re also obviously very much stiffer. I also reckoned that hookless beads would tubeless really well with the newer breed of tubeless ready tyres now bead tolerances are more carefully controlled and I think I was right on that count.
So, stiffness. Yes – they are stiffer. It’s the first thing I noticed of the Sultan, which I use as my big days in the hills bike. It translates as additional pickup under acceleration and a few rides of over-steering until you adapt. These effects seem to be magnified on the ‘orse a bit, and with it comes a little bit of small bump chatter since there’s no rear suspension. I supposed its possible that someone with a sub-optimally configured fork could feel the difference if the damping setup was a bit out. It feels like the tyres have too much pressure in them. I realised fairly quickly that the additional wheel stiffness is providing more trail feedback. If you’re the type of rider that spends a long time sat pedalling, it’s possible that you may not like the additional feedback or jarring. I personally don’t think it’s a massive deal, but it does exist. One of the reasons I don’t think it’s a massive deal is that the extra volume and width has allowed me to take approx. 4 PSI from my standard tyre pressures, which both provides increased grip, removes the chattery feel and doesn’t seem to affect the rolling speed. I’m 14.5st and run 20 PSI these days, which is enough for all but the biggest, fastest hits, like say, the Macmillan way on Exmoor in last year’s Mondraker Gravity Enduro, where I blew 2 snakebites (4 holes) through a Hans Dampf in one single hit (not a mark on the rim anywhere).
For me, the advantages far outweigh the slight adaptation required as a result of the additional stiffness. Its certainly not ‘break your bones territory’. How much you notice it will depend on how rough your usual riding is, and how perceptive you are as an individual IMO.