I live near the 400 trail and ride it often. I find it to be more scenic than the Elroy-Sparta trail without the tunnels. Yes, it is crushed limestone all the way from Elroy to Reedsburg. We had major flooding in the area last summer, so some bridges were washed out between Wonewoc and La Valle, but they should be repaired by now. If you are looking for some food try Trailbreak Pizza in La Valle - great pizza. Enjoy your ride!