Slightly OT, but if you can't afford the XPS line or want something which you can easily upgrade, I'd recommend looking for refurbed Dell Latitude series laptop

Slightly OT, but if you can't afford the XPS line or want something which you can easily upgrade, I'd recommend looking for refurbed Dell Latitude series laptops. I've been using an E7270 for the past few months with Ubuntu Mate and it's been flawless (uptime goes usually goes in 30-40 days). No port scarcity, adding extra RAM is just popping open the back panel and sticking it in there. It even has physical trackpad buttons which I like very much. Got it for less than $300, upgraded the RAM to 32GB DDR4 for another $100 and now I have a beast of machine for $400 that can easily handle anything. The only gripe I would have against this machine is there is only one slot for a NVMe drive. And the screen has some really chunky bezels but personally I don't mind that at all ;)