As Billy Martin famously said (in the Lite beer commercial), "I feel very strongly both ways".

I have a cheapie Allen trunk-mounted rack which I use on my rusty old beater. It's cheap and lightweight and easy to store away when I'm not using it. But it also leaves rub marks on the car's paint.

I also have a hitch-mounted rack for my WRX which cost a whole lot more because it also necessitated buying the hitch, something I wouldn't need ordinarily because I don't have anything to tow. But in use the rack itself is a breeze to use! Much faster and more secure than the Allen.