Hey guys, Just purchased a 13" base rMBP lately - haswell / 4gb ram / 128gb ssd. So I've been testing out the effectiveness and power of this machine just by opening up 7-8 native Mac apps (iTunes, iPhoto, the entire iWork suite safari and Safari with 5-7 tabs), and I gotta say that I'm quite bewildered and not very impressed by the apparent UI lag - such as using gestures to scroll back and forth on safari when those apps are in the background, especially when I thought those apps are supposed to be optimized!!! Not sure if it's the ram or the gpu being the bottleneck, but I can't help but consider returning this machine for the next tier model. Any input from anyone experiencing the same issues??