Frederic Malle Vetiver Extraordinaire is probably the best, brightest vetiver available, but it isn't cheap. Lasts for a good long time.
Chanel Sycomore is a warm, smoky take on vetiver, like a bright sun on a foggy day. It is my favorite vetiver fragrance.
Lalique Encre Noire is a cooler, smokier, grassier take on vetiver, but similar to Sycomore in many ways. The top notes are truly reminiscent of the smell of black ink. And some folks are drawn to the Iso-E super, which EN has by the bucketful. Also the most affordable of all recommended thus far.
Tom Ford Grey Vetiver, to my nose, is a more subtly vetiver-y scent. It is not a bad scent, mind you, but the vetiver is part of a bigger construction. And if longevity is your goal, this one is middling in that regard.
Mugler cologne, same deal... vetiver is there, but it's part of a broader soapy/floral fresh scent.
Hermessence Vetiver Tonka is exactly what it says... two classic notes blended carefully with a few dashes of complimentary scents. If you like grassy vetiver mixed with the vanilla/hay accord of coumarin enough to spend the money, this is your juice.
I've only given Fragonard's Vetyver a cursory examination, but it seems to be a well-constructed classic cologney vetiver with a nice woody finish. Can't speak to its longevity.
Parfums di Nicolai makes a Vetyver too. Has a spicy, mildly bitter herbal quality to it, which contrasts nicely with the sweet warmth of the base. Also doesn't last that long.
Edit: And now I notice that this thread was started over a year ago... Look at the dates before you respond, people!