Is there a comparison between milling machines and software?

Hello:

Has anyone had experience comparing actual speeds milling 3D objects
with the range of milling machines under $5000? I am trying to
determine how long it would take to mill a 3D object like the
examples on the Roland website
http://www.rolanddga.com/products/3d/combo/mdx15/mdx15_features.asp
(3D Max head, Lightwave cow) using other CNC mills such as:

Sherline
www.sherline.com

MacNc


AcuMotion Mills
http://www.acumotion.com/products.htm


MicroStep Mills

Model Master
http://www.modelmaster.com/

I have consulted the webmaster for Desktop CNC www.desktopcnc.com
also. Such a comparison does not exist yet.

I am trying to figure out how quick you could mill a rough pass and a
good pass for a 3D model (STL STIS, or DXF format) such as the model
Creature Lab dinosaur at
http://fxrealm.temp.dataphone.se/index.shtml.htm The model could be 6
inches in height, 4 inches in width, milled in foam, modellers wax,
or wood.

Also, has anyone done a comparison of milling software?


Thank you