I haven't had a chance to ride these yet so I don't have any commentary.
Location: Moab, UT
Directions: Drive south on US-191 for 16 miles south of I-70 (about 15 miles north of Moab). Spot the parking area on the west (right as you head toward Moab) side of the road. GPS N 38° 39.381' W 109° 40.672'. Park in front of the railroad tracks, and head out west on the road.
To leave a shuttle at the Poison Spider trailhead, go 6 miles down U-278 then right up a short dirt road with a sign that says "Dinosaur Tracks." GPS is N 38° 31.917' W 109° 36.473'. (from Utahmountainbiking.com)