Mr Gnome,
Being on a shoe string [ nothing wrong with that - it may alter ] take a look at Cut3D from Vectric.

http://www.vectric.com/WebSite/Vectr.../c3d_index.htm

Read the blurb and then you can download a working demo package and do the tutorials.

http://www.vectric.com/WebSite/Vectr..._tutorials.htm

This will give you a very good insight to what it can do.
The demo package will generate code but only for the models supplied, you can use your own model to see what happens but it won't generate code for it.

It will also do 4 sided machining as you mentioned to Robin. A 3D CAM package that will run 4 axis is very spendy.

From memory the Roland packages were very crude and only to show students what was achievable, not what was achievable as quality. Remember some of this file could well be running for 5 to 8 hours, something not possible in schools.

BTW do you have a signature or name ?