I have the 38's with ck hubs no powertap. Unbelievable wheels. Dave and Mike were both great communicators. Originally I was purchasing a complete bike and had ordered the wheels with a different color hub, then plans changed and Dave had the forethought to email me and ask about a change before final order. Super nice and personal considering how many customers they must have. The wheels are built perfectly, and seem very strong. They climb incredibly well and are light. I only have about 250 miles on them so far but I recommend strongly. These guys will stand by their products. I will be ordering a set of the FSW's as soon as the stock hubs are 11spd compatible