i'd agree a good rider on the xtrainer can be fast, having seen trevor campbell in the video below getting some good air on an mx track even with the stock suspension. but it was interesting to see that while he looked fast on the endurocross track, his lap times were slower than the ones where he rode a RR480. i suspect the gap would be at least narrowed if the xtrainer suspension was beefed up.
TREVOR CAMPBELL: BETA XTRAINER: https://www.youtube.com/watch?v=YuGrHr0_IkI