Man tough question.There are so many variations, and so many different themes, on this note that your going to get alot of varried opinions on this. Guerlains Vetiver, the first one, once you get past the heavy tobacco note is I guess about the truest Vetiver note you will find. In fact that has always been a complaint of mine with this frag. that the tobacco note is so strong, that I always thought that it weighed the Vetiver down, and detracted from the Vetiver note so much, that even as good as this frag. is, it could have even been better.
Which is why I like the reformulated version a little better. Yes it does have a bit more Citrus, but at the same time less Tobacco. Vetiver is one of my favorite notes, and one thing I can say for sure is that your going to smell alot of great fragrances in your quest to find the "pure" Vetiver note. Happy hunting!