An article was just published the other day in which the International Olymmpic Commitee and the International Society of Sports Nutrition concluded that they do not recommend the use of BCAA supplements.
I published a podcast about this
I have been banging the table on this for years. I cannot think of one reason to use BCAA supplements. Instead, use any of my protein powders to increase muscle protein synthesis.
Here is another study for good measure.