I think it's a matter of preference. Clen works very well but makes me feel a bit lethargic and anxious. ECA (ephedrine, caffeine, asprin), imo, works nearly as well but gives me a boost for training and helps control appetite a bit better. You can't stay on one forever, and, they hit some of the same, but also some different receptors. I'd try both separately and see what you think.