Honestly I used to take Arginine some years ago, and it did nothing for me. Perhaps I didn't take a high enough dose, but I don't think that a higher dose would be worth the money. Really, you'll be getting plenty of amino acids if you're doing proper nutrition.
Maybe though perhaps because I eat well (my mom is a professional dietician so I gained good habits as a kid) I am already at an "optimum" level or something, so Arginine might have benefits for other people. I just know that it didn't do anything for me.