By hanging upside down I consistently get moderate pain relief for my back and a surprisingly relaxing experience. I've spent two years with my Ironman Gravity 4000 Inversion Table and for $200 it is a good time.
Hanging upside down is supposed to perform a simple version of the fancy mechanical traction physical therapy folks performed on my back. The inversion table allows gravity to pull apart vertebra that have compacted during upright use of the human body. I far preferred the idea of this type of stretching at home, rather than the PT office. Largely, I prefer the idea of everything at home, except company. So, I ordered the Ironman 4000 in 2012, at the tail end of a fairly painful episode.
When I felt healthy enough to build the fairly heavy table, I found it was really pretty simple. The frame is super sturdy and super heavy. It is a simple folding design, like a card table, however and very easily set up. The swinging table was awkward to get into place, but easy to bolt on thereafter. I spent more time cutting protective packaging off the thing than I did setting it up! The table is really well padded and very comfortable to lay/hang on. The materials are all 100% confidence inspiring. This table is well built.
Absolutely nothing I have read recommends taking your first swing in an inversion table to full inverted. Every single source I read suggest starting with a mild incline and over the course of days to weeks working up to full inversion. Many even suggest going fully inverted is not necessary and that people feel wonderful results with several 2-3 minute 60deg inversions a day. I climbed in the chair, clipped in my ankles and immediately swung 100% upside down. The blood rushed to my head and I thought it might pop! There was no positive benefit to this except it was fun. The instructions also tell you to come back up slowly and to give your body time to adjust to being topsy-turvy or turvy-topsy, whichever is which, I certainly did that.
I slowly worked my way to fully inverted with daily use. My back doesn't feel so much "better" as this is a restful, relaxing activity that stretches minors spasms out. I notice that when I am regularly, 3x a day or so, stretching for 2-3 minute intervals, that I stand up faster and I'm not as limping/hobbled when I first awake in the morning. If I am having minor spasms the inversion table can help calm them.
A surprise side-effect is that I find hanging upside down like a bat to be relaxing! REALLY RELAXING! I do not worry about falling asleep inverted, that is simply not happening, however as soon as I get out I am hit by a wave of awesome dopiness. I love to go lay down, read a book or just take a nap. YMMV.
Inverting should not be mistaken as a cure. My back will forever pay the price of my unwise yet pretty exciting youth. My Ironman Gravity 4000 Inversion Table is a wonderful tool to hang me upside-down while I relax.