Remember that the lower the profile of the tire, the harder/worse the ride will be, especially on the LX/EX. You will have to go with a very low profile tire on 20" rims. Also, your rims will be more susceptible to being bent when you hit something in the road like a pothole. On the other hand, 20" rims will look better IMO. It all depends on your priorities. One of the reasons I chose the EX over the SX was that the ride was slightly better because of the 17" rims. I second the idea of going to the Tirerack site if you decide to move in this direction. In terms of tire width, wider is not generally better on an SUV like the Sportage. Narrower tires are better in both the snow and rain than wider tires. I'd strongly recommend going with a similar width to what you have now. Good luck.Has anyone done a 20" wheel upgrade on their 2017 Sportage LX? What tire size did you end up going for? I'd love to see pics! I'm unsure of where to start for this upgrade.