I want to order my new 27" iMac but im wondering whether there will be a big performance boost if I got to a i7 3.4ghz ? instead of the i5 3.2ghz ? and is it worth upgrading the graphics card to a gtx 680mx ? Alls im going to use it for is editing and uploading to youtube alot of graphics work on photoshop and illustrator ect and maybe some motion design on after effects. Will the i5 and gtx 675mx do me well or will I need to fork out more money ? I just want to know your opinions on this if you were in my situation ?