I purchased this despite the warnings of its being uncomfortable. Here is my list of pros and cons:

Pro:
--DOES compress. You can pull this very tight.
--You can feel it squeezing your hips together.
--Seems to be well-constructed

Con:
--Can't wear it over clothing, unless you are wearing something very long and loose
--It dug into my skin and gave me horrible chafe marks
--If you are wearing it correctly, it is literally painful to walk in. I tried to loosen it up for walking, but this defeated the purpose.
--I have a dislocated feeling in my hip now when I walk, and I wonder if the product was to blame. However, having worn it infrequently (though on 2 long walks) I am not sure.

My experience:
I could wear this for 2 hours at a time, max, and dreaded putting it on so much that I avoided it. I got it at around 2 weeks postpartum, and I think that I wore it 4 different times.
Despite not wearing this, my hips are nearly back to normal--I have 6 lbs left to lose until I am at my pp weight, and I am 5 weeks postpartum. I can wear my jeans again, so I don't think that I can give it any credit at all.

Conclusion:
I would skip this product in retrospect, though I know postpartum women (like myself) are quite desperate to return to normal, so buy it if it will make you feel better, but don't expect much.