I have been taking the Source Naturals extract ( 6 pills a day in 3 doses). I have not noticed a thing in over a week - I just ordered the Desert Burn so hopefully that helps. Not seeing many guys on this thread, so I thought I would give my 2 cents from a guy's perspective - I am thinking that the Desert Burn will allow for a higher dosage and that at my height/weight/ and appetite level, this could be the ticket!