i have found that with the grand trunk ultralight(no stretch hammock) I have to hang more with my feet up and it feels more like the ground with a slight space between my but and mid back. This causes a stress point for me unless i am feet up and back flat. On the contrary in my nano 7(stretchy hammock) I sleep better because it MOLDS to my spine thus there is no gap. It does squeeze my shoulders more but everything else is fine. I also dont need to hang super flat and can except a little curve with my head end higher. I think this is because of the stretch and "form fit" of the stretchier hammock which keeps friction on my back keepin me from compressing my spine even though in banana curving.