FG XC is a lot of fun on the the right trails. Navigating tight twisty singletrack with good traction, keeping your hands off the brakes, gives the trail a sense of flow that you can't get with a FW...makes it feel like a new trail. Technical obsticles, and steep hills start to get really annoying, however, when there are a lot of them, and even simple things like a small log pile become a big PITA because of pedal strike. You could argue that riding fixed on technical trails increases your skills, but not any skills worth having, IMO?