I have the x-fdd and an x-rd8(w) I laced into 26" wheels for an 80's mountain bike. Both in the 70mm drum which stops 95kg me plus bike and gear in as short a space as any rim braking bike I own. The nice thing about them is how smooth, quiet and reliable they are in any weather. I would highly recommend using them with longer levers, you won't have to squeeze harder but will have that much more mechanical advantage. I never got around to getting dynamo lights so can't comment on the dynamo output. I've read that the new rotary shifting 5 speed drum hubs (rx-rd5) have stronger internals than the x-rd5. There's also a rotary shifting 4 speed drum hub in the latest line-up.