Both will undoubtedly fuck you up, but I gotta give it to stalagmites- liable to trip over those pointy shits. May also give you diarrhea in Carlsbad Caverns.
Got an acute case of Cave Fever this summer? Stop by Acreage and peruse "Dark Fuckin' Cave," a foray into the equally-risky worlds of spelunking and petty retail theft. Get all over Twoacre, pronto.