I have the Performance XPort 2 bike tray hitch rack and use the dual hitch and bike locks below. I love it. I have my bike racked before some riders with roof racks have their front wheels off and leaning on their cars. I also leave it on the car 24/7. To beowulf7...The anti rattle comes from tightening the hitch bar wich is a screw on so what you're asking about is unnecessary.
You'll still need a 15mm wrench to tighten up the screw hitch from time to time but it's no big deal.
http://www.amazon.com/SportRack-A320...sg_ai_-2_5_tit