Funny you guys should bring this back up. I am still enjoying the awning, and it has held up great over the past 8 months with it on the truck continuously.
The only issue I've had is in wet weather a time or two one of the twist lock legs would not "lock out". I called up ARB and they sent a replacement no questions asked.
With all that said, I am taking a hard look at upgrading the awning to a howling moon aluminum hardshell awning with a canvas wall set. The HM is supposed to be overall a higher quality piece (the price reflects that), and I like the awning being encased in an aluminum case as opposed to a PVC bag. The canvas side walls convert it to a nice shelter in the event of wind+rain, or sun coming in at an angle. May seem frivolous, but I am really particular about my gear.
I think you'll have a hard time mounting to the factory roof rack. I'd strongly recommend checking out Bajarack, which will easily accept awnings with the brackets they sell (I use them and they are rock solid). Plus you'll have a much more versatile and usable roof rack.