I use a Jasmine Easy Spinner with a 18" hoop and that works perfect for me. I quilt small and big items in it.
Important for me is that the floor stand has a robust construction and it stands firm on the ground, even if a big quilt hangs down from the hoop. Because I only quilt in one direction I need to turn the hoop very often and the floor stand has to be robust.
I sit on an office chair which is adjustable in height.