LOL...
That is a question that people may be afraid to answer due to backlash. They are both great cars and will have not problem getting you to the podium. I have heard the Kyosho is really good on tighter tracks. I haven't raced any of them, so I don't know for sure what he difference in performance is. My guess is, it depends mostly on what brand you prefer. I race Kyosho only because it is more exciting, for me, to have the least popular brand on the track. The only issue I could see with Kyosho is the lack of support. It's not an issue for me because I like to figure it out for myself and/or I can always ask questions on here. Try throwing this question out there in both the MP10e and the XB8e thread. See what they tell you. Same goes for the nitro variants. Some of those guys have raced with both.