I've been wondering for a while now when Arrma will pull and XO-1 out of thier hat. It would be easier for Arrma than it was for Traxxas too - the Typhon/Senton platform would only need minor mods. Plus add a Fazon-style body, and an undertray, 40t spur, and belted slicks, and done.. The current power system is proved for 100-120mph. Maybe use the BLX200 system instead of the
BLX185, but I don't know if that is really needed, or if it would give any extra top end.
16/40 gearing would give it about 60mph out of the box (depending on wheel size), and drop a 26t in the box as a speed pinion to let it hit 100mph. Sell it for 1/2 the price of an XO-1.