Im a long term Zbrush user and am gathering some research information from users who use both Zbrush and 3DCoat. This thread is not X vs Y war, but rather an informative look at what are their strengths, and how these strengths aid in choose what app is more suited to one person or another.
Some of the things im looking at are as follows.
1: Pure sculpting Mesh based and other technologies, and feel of brushes
2: Fast base mesh creation
3: Freedom to concept sculpt
4: Intuitive navigation in the UI
5: Innovative features that are unique to each program
6: Reliability, stability, and performance
7: Workflow between other apps
8: Extra features no directly related to sculpting such as posing, Uv, re-topology
9: Cost and value for money inc cost for upgrades
10: Customer support
11: Commercial Training