If you want to buy one you should extend your analysis beyond the hardware specs because the software and operating systems are not ready yet. I can give the example of the latest XPS 13 2-1 where Office applications like Outlook cannot recognize a monitor with a different resolution and the fonts are blurred. Look for example at https://support.office.com/en-us/article/Office-apps-appear-... high DPI is a whole issu…
I just spent 30 minutes this morning dealing with this exact issue on my laptop that I've docked into two nice external monitors.
To fix it, open the display settings and set one of the external monitors to the primary display. Then log out, and log back in.
I have no idea why this works, but if it hadn't I'd have chucked the laptop out the window by now. Windows 10 is almost great, but for a dozen little stupid things like this.