I am considering buy a Zodiac HDS, but was test flying one yesterday and found the seat very hard on my back. Basically, it had to be lowered a bit so my head wouldn't hit the canopy (and I am not that tall - 5'10" or so). But the lowering is accomplished by just the lower part of the seat moving down, causing my butt to be in the bottom of a V shaped seat. This was hell on my lower back. I've thought about just putting a pillow behind me for some lumbar support, but are there any other tricks people have used to solve this problem?