Hi there! i own an x10, and it is a superb car! its just a shame about some of the quality of the parts, for example, dodgey drilled holes on the front gear box top, not on all of them, but on some (ive had at least 2 or 3 of these
).
However! since team extreme have bought the car, more money has been spent on sorting these things out and making a better car all round, a nice new gearbox top, part of which is cnc aluminium (i think?) sorts out the dodgey holes.
There are loads of other nice features on the x11 aswell, such as proper hinge pins, a spur gear which fits correctly, new rockers, i could go on and on!
like franki said... try the-pred website, all the info on both cars is on there!
hope this helps!
Tom