Quite simply, how good IS the retina display screen? I need to know for a sketching business I do on the side. I need to constantly switch my view from my laptop screen to my art table, so I want a really good quality screen that I can zoom into pictures while still seeing details, that also doesn't have much glare or reflection; I know the retina displays are crazy high resolution, but are they extremely glossy/reflective? I work in an area that needs lots of light. Thanks.