This. I tried using a Dell XPS and a Thinkpad as replacement to Macbook. But had to return both because I just can't get used to any other display after using Retina display, specially because the laptop is my TV as well.
The XPS and Thinkpads have both offered 4k for a few gens now. The real question is when Apple will offer matte screens. I can't stand the glare on the Macbook screens.
I don't think the current XPS:es have a matte screen option, last I checked the only ones with matte and known brand names and professional specs where thinkpads with low-res screens.
XPS:es have superb 4k displays too, but you might have got the version with a 1080p. Retina is after all just a marketing term for "High DPI", with no real standard for what "High" is.