Im kind of in the same boat, pay more for CDI than I paid for the whole bike when I don't know how good the engine is, but, im certainly not going to pay 300 used taking someones words that it is good, there's not even a test for that, how does he know its good, and even if it is good , for how long. I have been dragging my feet on this one, but I think im going to have to buy a new one for 400. If you come up with another option, please let me know.