Neither is really right or wrong. It all depends on how the caffeine affects each person, I guess. I've used an ECA stack for about a year now, and I think it's helped immensly! Make sure you drink A LOT of water though, especially when working out, because you'll get dehydrated a lot easier (from the caffeine).

I've used Ripped fuel, Metabolift (cheaper but hard to find), and Stacker 2 with basically the same results. As long as you don't have high blood pressure or any of the other risk factors on the bottles, just make sure you don't get anything that is "Ephedra free" because then it's about the same as taking a very expensive caffeine pill!

About cardio, I usually do it seperate from my weight training (in the morning) on an empty stomach (after taking the eca stack and drinking a lot of water). I know a lot of people who do it whenever they lift weights at the gym, though. I think it's best to lift weights before cardio if youre doing them in the same gym visit, to deplete more glycogen, so that you'd be burning more fat during the cardio than glycogen. I probably screwed up the explination but I hope you got the idea.

Good luck!

Michelle