I never liked clen, for some reason i just hate the way i feel while on it. T3 is great if you know exactly what you are doing, while using it. If you don't have your diet on point (while on, and definitely post use) you will not lose enough to make it worth while, or you will gain back more than you lost. I made a lot of mistakes when i was new to T3, so i am speaking from personal experience. Also when using T3 i was tired all day long, like i was jogging the entire day. I wont get into the whole ramp up/ramp down thing, because their are so many different views on that. all in all i haven't used either in a long time, i feel you can get the same great results, with a well thought out diet, a proper work out plan, and a good e/c/a stack. CJ