If you're looking to get leaner then you should be looking into your diet and cardio as to why you are not progressing.
If you're looking to build muscle mass and/or gain strength you should be looking into your diet and workout routine as to why you're not progressing.
You should not be looking for stronger supplements to make you lose weight faster or gain muscle faster etc. Supplements (especially the legal kind) are an aid to your workout/diet/training/sleeping etc. They are not a crutch and will not make up for lack of effort in other areas that are critical to overall fitness (no matter what your goal is).
That's just my 2 cents. But if you're looking for the best bang for your buck fat burning stack I would say the good old ECA is hard to beat.
This stack must be cycled because as mentioned earlier you will build a tolerance to it and taking too much is definitely not good (as well as the effects will be diminished over time).