Clen will definitely help you bust through your plateau bro. I took 100mcg on the very 1st day, and stayed in that dose range for the next ten, the sides mentioned above were quite tolerable, but then again, everyone is different, so start low, and increase the dosage accordingly. It's an awesome drug. Abs started popping out on my 4th day on it, (i was probably around 13% BF before i started though). And you get an extra kick lifting weights and doing cardio too (thanks to its effects on the Beta-2 receptors in the lungs, which causes bronchodilation, or in other words, opens up your lungs for more air). Mix Clen with your pre-contest diet, and cardio and you're well on your way. Good luck with the contest!
*But as with all shortcuts in life, there comes a price. Clen is a good tool in a pinch, like your present situation. But don't rely on it too much. It's been known to cause cell necrosis and fibrosis in animal hearts. That's cell death and scarring bro. Definitely not something you'd want. Natty is always the best way.