Hi, I'm new to this forum. I am an admitted Apple fanatic--I've been hooked on Apple products for years. iPads, iPhones, iMacs, MacBooks, Apple TVs--we have 'em all over the house. When the new 12-inch MacBooks were released, I was hit with upgrade fever, so I recently purchased one to replace my 2009 MacBook Pro. I loved the weight and size of the new MacBook, and that Retina screen was gorgeous! This being my first-ever Retina, I marveled at the crisp clear text and sharp images. I fell in love with this machine, despite its flaws. If you read the previous paragraph closely, you will see that I referred to the MacBook in the past tense. That's because I no longer own it. Shortly after using it, I noticed headaches and eye pressure. I Googled it and discovered that I am not alone--hundreds of other poor saps like me cannot tolerate a Retina screen. Millions of people the world over are happily hunched in front of their Retina screens with nary a blink. The unlucky few like me develop headaches and eye problems. Nobody can really say why. Some say it is screen glare; others say it is the low refresh rate which causes flicker. The best way I can describe it for me is that the text has a 3-d kind of look--like the text is so sharp that it looks like it is set forward on the screen as in a 3D movie. After using these Retina screens for a couple of hours, I feel as though my eyes have "burn in". There is no clear explanation, but there is a LOT of anecdotal evidence. I am not alone. I did try--I used that beautiful space gray machine for a couple of weeks, hoping I would get used to it. But my headaches did not abate so I finally surrendered and sold the MacBook (made a $100 profit, at least). But my upgrade fever was not satisfied, so I set my sights on a MacBook Air, which is similar to my Pro but much less beastly. Searching eBay for an Air one day, I came across an auction for an iMac. We have a 21.5 inch 2011 iMac; it is a perfectly fine machine, and I was not looking to upgrade that. But this auction was such a good deal that I could not pass it up--a late 2015 Retina iMac, 21.5 inches, with 2 years remaining on Apple Care, for $825 shipped (it was a very poorly-written auction, thus it escaped notice; I just happened upon it and nabbed it). Factor in the 8% off eBay coupon I had, and I picked up that machine for about $760 total. Well, I thought, maybe the bigger screen will be more forgiving. About a week later, the iMac arrived. I set it up and have been using it for about 2 weeks now. Same problem--headaches and eye pressure. The thing is, I have absolutely fallen in love with the crisp clear colorful gorgeous Retina screen, and I'm having a hard time going back to my old iMac and MacBook Pro (curiously enough, I have been using iPhones & iPads with Retina screens for years and never had any problems...) So, here are my questions: For the desktop--If I purchase a 27-inch non-Retina iMac, will that screen be a significant upgrade in resolution and clarity, since it has more pixels than my 21.5 incher? I'm looking for a compromise--if I can't use Retina, perhaps a bigger screen will be sharper. And how about a late model MacBook Air? Will its screen be a significant upgrade over the MBP 2009 that I have? Also, I want to buy a separate monitor to use with the eventual Air I will have--one that is better than my current iMac but not as sharp as a Retina? If so, which monitor would you recommend? Any thoughts (and condolences) are welcome; thanks!