PIE menus are very useful! I am using Realsoft3D and it has PIE menues (called compass menus in RS3D), which makes it very easy and quick to find the right action or method for the object to edit. The best thing is, they are customizable. So, every user can change the PIE to his needs. One of the best features regarding this kind of menu is: They are context sensitiv. So, if you click on a Subdivison-Surface, you only get the tools for SDS. If you click on a curve, you can select curve tools. This way, you don't have to move around with the mouse and find the right tool or menu. Certainly, this would be very handy for TG2. Ask the users of Maya, Realsoft3D or any other major 3D software. They always use this kind of "menu".