The third bed back in this picture...
with the crossed and zip-tied PVC was the easiest and fasted frame. Not cutting involved! The fellow in the picture just shoved entire PVC pipes down into the corners of the garden bed frame, diagonally. After a big storm it had leaned a little too much so he zip tied the pipes together on the top where they crossed. Be sure to try bending the PVC before you buy it.
It was the easiest one to store too because there were fewer pieces.
We had lettuce all winter! Even gave a bunch to the food bank!