Up until recently, I had two bike racks: an old Nashbar single-arm triple rack that mounted on the hitchball of my Mazda pickup, and a Thule double-arm double rack that mounted (poorly) on various sedans. The Thule rack was not particularly stable, had a spiderweb of mounting straps and had an annoying tendency to sway and let the bikes hit up against the bumper and against each other. The Nashbar I bought back in the 80's, and the frame cutouts on the mounting arm were designed for cro-mo bikes and had difficulty in accommodating my fatter-tubed aluminum bikes.
I recently bought a new road bike (Motobecane Grand Sprint) and was thinking about a quicker type of mount that offered easy on and off and was more stable. For quite some time, I had been looking at the Sportworks and Thule hitch mounts in which the bike sat in a tray, a arm clamped down on the front tire, and a strap clamped down the rear wheel. I had seen a demo model once, and liked the way that the bikes were held down solidly with no frame contact. These typically cost around $ 375 or so, and were made for 2" receivers. Unfortunately, I have only a 1.25" receiver and all the rack manufacturers said that a receiver adapter should not be used.
As luck would have it, I was in the downtown Seattle REI store three weeks ago and saw a new two bike rack by Yakima in their rack catalog: The Hookup 1.25": http://www.yakima.com/Product.aspx?id=102 for $ 359. And even better, I could use a 20% off member coupon for the purchase. 15 days later, I had my rack delivered and saved $ 71 off the purchase price.
It took about 20 minutes to assemble and install. It would have been quicker, but I had to partially disassemble the receiver assembly to allow alignment of the locking pin. It weighs about 50 pounds and each bike tray can support 55 pounds. It seems to be of absolutely bombproof construction: very heavy gauge steel and aluminum and sturdy plastic bike trays. It literally takes all of about 20 seconds to load a bike and secure it. The bikes ride upright and do not contact the car or each other. It fits securely into the receiver with very little sway. By removing the locking pin, you can fold it up to an upright position. I have taken it on the freeway, and neither the bike nor the rack moved at all during the commute. I also bought a cable lock to lock the rack to the hitch and the bikes to the rack.
So far, so good, and this may be the last bike rack I ever buy. I am pleased to see more of these racks now available for 1.25" receivers, although you may have to search to find one. No one locally carries this type of rack, and it seems as if many of the online vendors only carry a 2" model. The 1.25" receiver model carries two bikes, and the 2" receiver model can accept two auxiliary trays giving it a four bike capacity.