I don't see how anyone can call this a developer edition laptop if it has the same keyboard as the rest of the XPS line. XPS keyboards are mushy chiclets with big gaps between keys.
Meanwhile, Dell's Latitude line has excellent keyboards, at least as excellent as you're likely to get in a laptop these days.
I've always been a fan of the Latitude series, they are (in my experience) the best combination of quality components, cost efficiency, and are easy to repair/upgrade. The only negative is that they tend to lag behind Dell's other series when it comes to having the latest CPU/GPU.
From Dell, no official support, but my experience over the years has been that they are well supported by the Linux community for network drivers and things like power management (sleep/wake). The biggest downside (for me) is the lack of a good GPU beyond the Intel HD series; the models I've dealt with are most often equipped with Quadro NVS chips. The NVS just barely outperforms the Intel HD series, but requires the closed source driver to do so.
I haven't messed with them since the Sandy Bridge days though, so your mileage may vary with more recent models.
Meanwhile, Dell's Latitude line has excellent keyboards, at least as excellent as you're likely to get in a laptop these days.