I am looking at getting a 2019 iMac 27" to replace my 27" 2015. Besides the normal web surfing and office stuff I use Lightroom and Photoshop. Once in a while I may game with X-Plane. I think the Radeon Pro 580X should be good for me. Or do I need to be taken into the Vega 48? Where do you see the difference in the 2 cards?