Just an FYI for those considering the 11" for music production. I just picked one up (Stock with 4GB ram 1.4GHz processor) and just did the included "Helena Beat" demo test by Foster The People (74 tracks). I added an additional piano and just played arpeggios during the whole song - and I stayed at around 61% CPU idle in activity monitor. Ram stayed in the green. I also had Radium open and playing an internet stream radio station...as well as Facebook, safari (only 1 tab), Leaf (RSS reader), mail, and a PDF in preview. This is all using the included logic pro 9 instruments - but this little machine is pretty amazing! My 15" 2014 retina has been sitting on the desk looking pretty lonely since I got it... Anyway, just a heads up for anyone curious! Oh - and this was all on battery!