After tons of research I decided to go with the rack that continually gets the best reviews. It turns out it was no mistake. I bought a
Sportworks Mod Series. It is top rated at
Mountain Bike review. What makes this rack and others that are similary designed, superior to others is the ease of getting the bike on and off. You can literally mount the bike in 15 seconds or less. No removing the front wheel, etc. like many other racks.
Also it is much better to have the bike secured by the wheels than the top tube like many other carriers, like the Thule. I just hauled my bike again this weekend at speeds near 80 mph and it is solid as a rock. My rack also has the folding hitch so it can fold up when you don't have the bike on or fold down if you need to access a rear hatch etc. (not an issue on my car since there is room to access trunk with bike mounted) I HIGHLY recommend this rack!