Alright, so this may seem like a dumb question at first, because obviously the 13" rBMP is going to be faster than an 11" Air (mid-2012). But my main concern is more about UI responsiveness and lagginess. I've read things about the 13" rMBP with scrolling, switching spaces, etc due to the weak graphics card powering such a high resolution. I currently have an 11" Air and am thinking about going for the 13" rMBP, and I'd just like to know if the lagginess of the UI can compare to the 11" Air in this regard. I notice a few lags and frame rate dips on my Air every once in a while (usually scrolling in full-screen Safari), but if the 13" lags some more with its higher resolution, I'm not sure I'd be able to handle it. Has anybody compared the two?