I recently asked if anyone I knew had one of the new models but got no responses (via my blog, or Twitter).
I've got an XPS 13 9343 and love it - largely form factor, but also the 3K screen - and have been wondering about upgrading recently, in part due to USB-C and fingerprint sensor, not for any other reason.
According to the Arch Wiki entry for the new XPS it's mostly alright, but doesn't seem to have fingerprint support.
May be that it needs to get upstreamed by the folks at Ubuntu.
In case it's a point of interest, the highest-end one has a 4K screen (RRP £1768.00)
I'd say go for the slightly newer one, with the caveat that if you stick with the Ubuntu build it comes with, it'll probably be alright, but if you want to re-install/install a different OS, it'll likely not work as well, and may require a more up-to-date kernel - as I decided to use Arch at the time it meant I always had the latest kernels, so as they added support for the drivers upstream, I was getting them pretty quickly, whereas friends with non-cutting edge kernels didn't have as much luck.
I really do recommend Dell for the XPS based on my existing one, and would be very interested to see how you get on with it, if you do get it, so it can inform my decision to buy one while I'm in quarantine and don't need my laptop to be as functional as I would if I were travelling.