I used all the above to make the tetrahedron that Katrina demonstrated for Christmas table gift bags.
The Therm-o-web was simple to use and effectively made the structure quite rigid.
I have made these 'bags' for my grandsons. They are 12 this year and well into TLOTR and play snooker and billiards with grandad. I will be filling the 'bags' with Easter goodies.