I am a big sceptic of all of these kind of things, but I did find that Hoodia supressed my appetite - the problem is that being hungry was not my problem, I still eat when I am full, becuase I have serious issues with food - thus Hoodia didn't work for me!
I have done lots of research on Hoodia and have found that very few places offer PURE Hoodia. If you look at the small print on most versions you will only be getting 25mg of pure Hoodia in a 400mg tablet. The rest is lots of different suppressants.
If you do buy any. Makes sure it is pure Hoddia Gordonio - from the stem and that the company has a C.I.T.E.S certificate - if they can't offer one, then the pills are not pure.
I definitely wouldn't take any pills while on SS and effectively with an empty stomach!