I asked a friend of mine who is a big time mountain biker. This is what he had to say:
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If they are looking for quality there are only two choices:
Yakima and Thule.
Go to a bike shop. This is an expensive way to go but it is the better way to go. Much higher quality and no risk. Most shops will also help you install it if you ask them too. Also, if there are problems they can service it. But with those two brands there are never problems. I would go with Thule but that is just my favorite. They are both pretty much the same.
The cheap way to go is to purchase a rack off
www.performancebike.com. The prices are dirt cheap. The quality is lower though. That is what I originally did. They sell the big brands but the cheap one is called xsport. Nothing wrong with that rack I suppose. But it is not nearly as nice as the other ones.
And I did have problems with mine. Road salt
corroded the locks and I really did not like the way it fit on top of my car. The Thule racks fit much better.
Best bet is to check out both options. Check out the website and go to a bike shop. Then make the decision. If you go with the xsport rack you lose some quality and of course all service because it is available on the website only. But you save a lot of money. If you go with Thule you get a guaranteed winner but can expect to pay around $400 dollars for a rack to carry two bikes with a wind fairing and a locking rack.
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Hope this helps.