4-Axis CAM suggestions?

I've been fairly successful doing 3-axis machining (Rhino > STL > STLWorks (demo) > CNCPro >Gecko 340) on my converted Tree Journeyman. So far I've just been playing but I want to add a 4th axis to machine some irregular shapes.

What concerns me is that some of the inexpensive CAM packages (Bobcad?) creates a 4th axis by substituting a rotary axis parallel to the X-axis for the Y-axis. The resulting G-code still only drives 3 axis, one of which is rotary. This seems like a waste and a loss of capabilities when CNCPro (and EMC) is ready and willing to drive all 4 axis.

Do I have this right? Do any of you have any suggestions for a low or higher end CAM package that will intelligently handle all 4-axis. Please be gentle... this is only a hobby.

Roger



[Non-text portions of this message have been removed]