Velocity Dyad rims - they build up very nicely, and fast because they are flat and round. Noticeably faster to build than Sun CR18 which is also a very nice rim. The Dyad is stiffer and lighter than the CR18.

Wheelsmith spokes - see Peter White's discussion (rant) on DT.

Hubs - now this is different from others: Wheelmaster Tandem 40H: http://www.amazon.com/Wheel-Master-T...1&keywords=40H also available in Black. This is a 135mm OLD hub, with a 14mm axle, turned down to 10mm outside of 135mm, with BIG sealed bearings. It is glued together like a sealed BB. 14mm axles are 3.8X times stronger than 10mm axles used on Shimano hubs. (axle strength is proportional to the diameter raised to the 4th power - yes, I am a Mechanical Engineer). The stiffer axle also means that the wheel rolls better because of less deflection in the bearings.