Yeah the OS X UI smoothness is great if the GPU is up to the task, like on my iMac it's flawless but in the case of this Macbook it's Intel Integrated graphics

Yeah the OS X UI smoothness is great if the GPU is up to the task, like on my iMac it's flawless but in the case of this Macbook it's Intel Integrated graphics on a Retina display, and in my experience that can be less than flawlessly smooth in operations like Mission Control/Expose for sure, so it seems Apple has some catching up to do now. I also find Windows runs very well on low specced computers. Safari on Mac OS is extremely smooth, from the looks of this blog it seems Microsoft has replicated that in Edge browser. Look forward to trying it.