Folks: Just bought a retina 15" and updated the OS immediately based on other posts here. Installed office too. Overall, great build quality, but... 1. If I open web pages w/ graphics, kaboom. Test: open nyt.com. Click on article. Expand size of text -- and then I get the spinning rainbow of doom for 60 seconds or more. Once the page finally renders in a bigger size, I can't scroll up or down without major lag. 2. In excel, if I page through a file w/ lots of data, I get scroll lag. This is easily repeatable and I haven't changed a thing (other than updating the OS and installing office w/ the retina update). I'm using the standard resolution that's retina friendly. At this point, I'm going to return it, and have no idea what I'll buy next. Any help appreciated.