I've tried samples of 3 different Lipo 6 products, and didn't like any of them. Epic headaches and jitteryness, and not much positive. I'm unusually senstitive to stimulants though, so that may have been the issue.
I've heard nothing but good things about Mitotropin though.
As Wren said, it's going to depend more on your routine and your diet than the supplement. I had great results with Nutrabolics Hemodrene, but my diet was the cleanest it's ever been while I was using it, and I was doing more cardio than I normally do as well.