We recently started stocking the SP dynamo hub after trying and testing them, I have been riding one of these hubs for nearly a year now and I have been nothing but impressed. Matching it up to the right light and other accessories this hub could take you round the world without ever having to change your batteries in your light or having to stop to charge your phone or gps unit.
The PV-8 is designed to be a low drag hi output hub, weighing in at 390g it is still one of the lightest hubs for its output type (This is for the non disc 32h version) Giving off a massive 6v/3W this can power a front and rear light without any trouble, it is also compatible with The awesome Cin1-5 usb port, providing more than enough power to charge any device on the more. Comparing the PV-8 to the SON Delux, they both way weight exactly the same however the SON gives less output and is only 65% as efficient as the SP which is 75% efficient in terms output to drag. The SP also retails at almost half the price of the SON version.
I have been running my SP PV-8 with a Son Edelux II headlamp, these have a 6V/2.4W “High quality LED head lights provide five times more light than the former halogen lamps, elaborate mirrors (reflectors) distribute this light perfectly on the road” according to Son. I cycle mainly on unlit roads and this produce enough of a beam to see without blinding other road users. A dynamo system would normally be found on a randonneur bike or touring bicycle, however I think they are perfect for everyday commuters and general cyclists the same, how many times have you gone out in the morning and forgotten your lights and then had to risk the cycle home with no lights? Dynamo hubs are permanently attached to your bike, as are the lights that normally work with them. There is an upfront cost of purchasing them and to some this might seem a little steep, but imagine never buying a new light again or better yet never having to replace expensive batteries in them. Grab your hub here or come into the shop to discuss wheel building options.