Awesome advantages to the system are:
1. When the rack is folded up (not being used) it sits just right so the trunk can still open without having to mess with the rack. I doubt you can do that with the Yakima or Thule racks because their trays are farther apart and the system is therefore taller when in the folded position. Being able to open the truck only works in the 2-bike configuration - if you have a 3rd tray on there it will no longer clear. 2. The trays are closer together because the trays are slightly staggered vertically. Also, the bikes are kept in place with arms that compress/hold the tires. You can offset each bike towards the front tire so they get more staggered to allow for handlebar/saddle clearance. My brother and I can't get our mountain bikes to fit on a Yakima rack without moving a saddle or adding a spacer under a tire because the handlebar of one bike hits the saddle of the other. That's never an issue with this rack.
3. Although all these racks are heavy, it is completely manageable in the 2-bike setting and very easy on and off - locking in position with an expansion bolt rather than needing to find the hitch pin.