They are fairly easy to install, yet I managed to slightly screw it up. The only reason I would recommend having a dealer do it is risk vs reward. Some folks, and dealers, have cracked the glass roof during installation. Thats probably a fairly expensive mistake. I am sure you could get it installed for 100-150 bucks. For me, in hindsight, I would just pay the dealer rather than risking the repair bill...that being said, if you are careful, you shouldn't have a problem...
As to the MY2013 just being open to order...wow...what a long wait, and for apparently little feature changes. Glad I didn't hold off on a 2013 and bought a 2012 a few months ago....