i'd get a worksman inb (was $350 shipped to my door, no fenders)
http://motorbicycling.com/f15/i-think-i-finally-nailed-28689.html and get a sprocket adapter ($90 shipped from sportscarpat here on the forums).
i had issues with mine that i simply wouldn't have had if i started with an adapter, cause i tried modding my bike to work with a kit supplied rag joint.
the worksmans are heavy duty as ****, have some of the best wheels on the market and look great too boot.
also if you get a worksman get it with the 36 tooth sprocket. good luck with what ever you choose.
if you go with a worksman i can help you with advice since i got mine all taken care of.