If you have a 2-inch receiver hitch, I recommend either Hollywood racks or the Swagman xc racks. I have had both and personally prefer the Swagman for convenience because it has adjustable loops that you rest the tires of your bike in as opposed to standard protruding bars that you rest the top tube on. This allows the rack to be usable with any style of frame, whereas a standard rack is incompatable with monotube frames like the the Trek Y-26. On the other hand, the Swagman doesn't offer any convenient way of locking your bike to the rack...which is a feature I really like on the Hollywood racks. Anyway, either of these racks are very nice options.
I bought Thule's Trailblazer 998XT and am generally satisfied with it. Conceptually I'm not crazy about hanging bikes off the back of the vehicle only because it promises to scratch the finish of the bikes. I prefer parking them on the roof each in its own carrier but I don't have room for a forklift in my garage. Clamping the family skiis on top of this beastly machine is tough enough.
Given that the Thule stands the bikes on posts you probably want to get frame adapter #982 if your top tubes aren't perfectly horizontal.
I remove the carrier after each use and after five uses I can properly mount the carrier and load four bikes in less than fifteen minutes. This swing away model does allow your open the rear door with fully loaded carrier. You will have to defeat the rear parking sensors when driving in reverse with the carrier installed.
RackAttack.com had the best price at the time I purchased my hardware. Price included shipping this 50lb. rack.
We bought a “Softride" 4 bike rack from outpost .com and with its parallelogram type frame construction it makes getting into the rear hatch with a rack of loaded bikes easy. It comes with a keyed pin lock to attach to the receiver + cable loop to lock bikes to rack and is very sturdy and was less than $200.