I use Hexagon for basic model creation and morph creation.  If you're going to get Hexagon, get version 2.1 not 2.2.  Version 2.2 is still broken because it screws up the vertex order on export.  2.1 works just fine.  If you're looking for a clay sculpting type modeling tool, Zbrush, Silo and MudBox all work well.  I prefer MudBox because it's really simple to use and you can learn it in under an hour.