...there are some folks who just are unable to make it in a hammock. Sadly, I am one of them. I spent a winter, spring and summer trying to make a hammock work for me. Got a nice flat lay, good quilt and under-quilt, and simply could not fall asleep in the wretched hammock(s)! Usually I would only fall asleep somewhere around 3:00 or 4:00 am, utterly exhausted, and then have the weirdest dreams I've ever had!
Also, as another sufferer of a wonky back, I found that a hammock did NOT help my back - but it probably related more to not being able to get a restful night's sleep than any physical discomfort of the hammock.
If it works for you, great! If it doesn't, you will at least have tried it. There are some real advantages to hammocking, like very low impact, no worries about flat places to sleep (just have to find two trees the right distance apart!). But in the end, for me, an Exped pad trumped a hammock for a good night's sleep!