So I've had some great success with alphamine+alpha t2.
Tried Norcodrene briefly just to test it out need to do a full run.
Right now I'm on an eca stack and its working well.
Wish I knew which worked best between the alphamine, Norco, and eca but you would need a laboratory.
Comment though on what actually is the "best"
To get proper comparative results you would have to hold diet and training strictly constant and take many measurements of progress.
I don't think anyone is willing to do that as there would not be a great payout.
We are restricted to saying and concluding what we "feel" works best.
Until someone wants to step forward with some tests, and at that point I volunteer to be lab rat

Important thing for everyone now is that what you're taking does as it promises.