The Great Debate: Natural v. Synthetic Ingredients

Okay, I'm going to go out on a limb here and start what could be a fairly large debate -- which is, after, the idea. I'd like to hear some opinions about this.I am a 29 year old athlete, and I take care of myself through diet and exercise. I have a full head of thick wavy hair, and for that I am eternally grateful. But as I try to do what's best for my body, skin, etc., I stumbled across the "natural v. synthetic" hair care issue, and it's one that seems to have no clear-cut winner, regardless of what each side would have you believe.I use Aveda's Shampure and Rosemary/Mint conditioner, ALONG WITH a host of natural products by Aubrey Organics. Aubrey's products are 100% purely natural, and for that I commend him, because he is the one of the only people out there dedicated to this notion. I've browsed this forum, and to be honest, I'm sort of surprised that there isn't more talk about Aubrey Organics. I see tons of posts regarding ARTec and Aveda, and I'd like to get some opinions on the quality/efficacy of Aubrey's shampoos/conditioners.My girlfriend has a book by Aubrey, in fact, called (something along the lines of) The Natural and Organic Method of Skin and Hair Care. In the hair section -- and throughout the book, really -- Aubrey makes it known that he knows his stuff. Anyone who has not read this book should read the hair care portion (I'd guess the skin part is just as good); it's very clear that Aubrey has a doctorate chemist's understanding of hair, its compostion, its growth, loss, and chemical makeup. It's certainly not Grandma's Shampoo Book -- it's very strong scientifically, and argues vehemently for the avoidance of all synthetic ingredients.Now, I find that Aubrey's stuff is quite good (especially their skin cleansers, etc.), but I still like going back to Aveda pretty regularly. My girlfriend does this too, as she finds some of Aubrey's shampoos are too drying for her hair.I guess my question is this: which camp is (more) right? I know there is not one miracle product out there, but surely a methodology behind a product's formulation (mostly natural v. synthetic) counts for something. Does anyone out there have experience with this issue?BTW, Aveda isn't nearly as natural as one would think it is. Ammonium Lauyl Sulfate, Lauramide DEA, Lactamide MEA, etc., are seem quite prevalently in its products. I'm not condemning Aveda -- if it sounds like there's any bias here, it may be because I just finished reading Aubrey's book regarding natural hair care, and he fervently believes that synthetic chemicals are toxic and should be avoided entirely.Thanks for reading this novel, and I welcome any comments.J.