I can also vouch for the Hollywood hitch rack. I have a two bike rack mounted to the rear of my Van using a 2" reciever. I also have the two bike additional attachment. I never manhandle the complete four bike unit assembled as it is quite heavy and with all the kids basicly out of the house now, I seldom transport more than two bikes at a time.
The rack has served us well on trips as short as 15 miles and as long as 2000 miles.