Ive tried it , only a small bottle when I was first starting out. Alot of my gains were beginner gains along with my excessive nutritional needs and just killing myself when I was in the gym.
So I cant definitively say it helped but , but it didnt hinder me. Im sure I would of gotten the same games as without at the level I was at when I took it.
Try it , but I dont see it being worth it and this was also only a few years ago so its not like delivery and absorbtion etc has been improved greatly.
Use the money on a clean whole foods diet , or staple supplements like protein , creatine. Or if you do decide to try it out get the cheapest bottle you can.