Aspire has 3D modeling tools, so you can create all your 3D models in Aspire. You can't do any 3D modeling with V Carve Pro and Cut 3D.
Also, Aspire does NOT do what Photo VCarve does, with the exception of Lithopanes.
And Aspire doesn't do 2 sided machining, but I think that Cut3D does.
But the major reason for the price difference is the 3D modeling stuff.