IMO the iPhone 8 plus would be the way to go due to its better hardware and larger display. In fact the iPhone 8+ has a larger screen than the iPhone X (in area) so everything is bigger when viewed on the 8+ which is good for my ageing eyes. I have an iPhone X and was considering going back/down to an 8+. I ran them side by side browsing, emailing viewing YouTube etc. The 8+ is definitely bigger but the surprising thing was just how much brighter and clearer the iPhone X screen was in comparison. This made me keep the X.