I have both. I do not like the 3-4 bike hitch set-ups, because they extend too far from the vehicle. I use a 2 bike hitch set-up. And I have roof mounts as well. The hitch mount is really easy to install and takes less time than the roof racks. Also - the bikes are out of the path of bugs and other road grime. But they are exposed to backing into something, or a car hitting you from behind. Really it is personal preference - the hitch mount is generally easier to deal with. And if you have a box up top there may not be enough room for bikes. So all depends on your specific needs. Both are good solutions, IMHO. I use both Thule and Yakima roof stuff, but prefer Thule. My hitch mount is a Yakima.