ZRX, I just last week tried this back brace for back spasms that were beginning to flare up (I've had it in the closet for years, first time trying it - I just happened to be looking for something else and spotted it..)
I like it -Its easy to get initially wrapped around, then you pull in the cinch strap (First pic), the "girdle cinch" in the back tightens up, and Bob's your uncle. All Velcro for the belt and the cinch, so very easy. You can adjust to the exact pressure you want.
It worked great and I only needed it most of one day - I may wear it again today as I'm feeling some strain back there.