Big Bad Wolf was definitely the better of the two.
Volcano was a nice idea, badly implemented; It started well, but after 20 seconds, it was out of worthwhile things to do.
Big Bad Wolf wasn't as spectacular as it looked, and was a bit underwhelming in some key areas, to be honest, but at least it was fun. The first half, zooming through the village was decent enough, albeit not groundbreaking. The signature big drop was somewhat ruined by trims, the turns that followed were pretty good, and then the ride just... ended. There was some good stuff in there, and some great individual ideas, but somehow, I never felt like it managed to be more than the sum of those parts.