beryld - I've head of Applo before, but hav'nt seen him yet.  Do you have a link, or more importantly a favorite render?

A higher resolution mesh means more points to which a texture map needs to be accounted for, hence higher(and much higher) resolution Texture Maps can be used; for bigger, and higher DPI, renders.  You would'nt notice this by say loading 10 V3 figures into one scene, and then only having enough PC resources to rendering a Screensaver sized image.  But when you get into Life Size renders you begin to appreciete Resolution.

I wrote a thread on Figure Vertex Counts a few weeks back.  When you load an .OBJ into UV Mapper, the first thing UV Mapper does after load is tell you the Resolution:

 V3, D3, and M3 - 72,712

 V4 - 67,619

Not much of a difference, but for any reasons not to make V3 and V4 compatible with any existing figure, the trend should have been an increase.