In fact i re tested now Sculptris and Zbrush process !
I go lot more fast making general shapes and some details in Zbrush by using Zspheres 2 that is incredibly fast.
Once it's done just make the unified skin and begin sculpting and detailling.
The problem of sculptris is when you go high on details and polygons it begins to be really slow.
But yes it's an enjoyable sculpting tool before using one lot more powerfull like Zbrush