Xray. This only heresay because the 11' is not out yet but the team drivers are raving about it. The issues with the diff cases has aparently been resolved. (Note I have NEVER had diff case issues, but some have) The drivetrain is smoother and the way the car reacts and handles has been greatly improved. I have had all generations of the 808 and it has been the most reliable buggy ever. It handles great and I have no complaints. The issue with spare parts really is a non issue with me. I have broken maybe 5 times in three years of hard racing and never the same part. So why keep spares if you will never need them? I have a friend that was sponsored by Xray and now Mugen and he says the cars feel very similar on the track and he's happy driving either one.