pzj99 is absolutely right in saying "it depends."  In the end, you may find yourself starting with one figure and migrating to another.... or not.  Personally, I started with V2, and bought V3 and then V4 when they each came out.  After buying all their morphs and then spending days (actually, more like weeks) trying to shape and bend V3 and V4 to my liking, I abandoned each one in turn and returned to my customized V2 figures... where I am today.  Of course, my hopes spring eternal that V5 will finally make me truly happy.