Check out Vectrics latest and greatest. 3D machining software.http://vectric.com/WebSite/Vectric/cut3d/c3d_index.htm
This includes one, two and four sided machining capabilities, Z level roughing passes, a slicing function that slices your model and then machines only the edges that need machining. ( a great time saver) and a bunch of other neat features. all at an affordable price.
I'm not affiliated with Vectric in any way, I just think this is another great product from them.
Here are a couple of sample I cut using the new software.
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