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.

It is one of the better laptop screens. There are also screen covers that can matte the screen so it isn't as reflective. I would go to your local technology store, best buy, apple store, or other computer store, and check out the different monitors. Is the operating system important to you? Does it need to be OsX? Or Windows? Or Linux? These might be deal breakers.

Talking to an Apple Genius at a Apple store is a good idea.