It must just be me, because I hear a lot of good stuff about spanx.  I'm 5'10, 135-140ish with a fairly muscular build.  I tried these on over my under-garments for a dress I was going to wear to a special occasion.  They felt uncomfortable/constricting and the fit in my hips was weird.  I do have some wide hip bones, but it didn't work for me.  I could also see the seam where it stopped on my leg under my satin dress, must have been the dress material because these are supposed to be seamless.
Anyway, I'm giving them 3 stars because I figure it might be a fine garmet, just not my cup of tea.