Unfortunately XPS Developer Edition does not support external 4k displays @ 60Mhz like Dell's own P2715Q. If that kind of thing matters to you.

Otherwise I think it a great machine.

I think people are talking new gen XPS here right? Think all of them have supported 4k external @60hz as they have nothing older than broadwell.

I'm sitting here now with a gen1 xps 13 2015 pushing a 4k monitor at 4k 60hz.

My xps 15 in work also supports 4k @60hz although needs an annoying usb-c to displayport dongle.

Afaik, the 6th gen XPS 13 supports even two 4k 60Hz monitors...

I've checked out the Macbook Air at the Apple Store a few times and I'm so close to just selling my i5 MBP for a fully spec out 13" Air. I like the idea of having such a light and still powerful system for web and ios development. From the sounds of it I wouldn't be giving up to much going with the Air over the MBP.

That's exactly what I did, and I couldn't be happier. It's so light that I find myself checking my laptop bag just to see if it's still in there. I went with the highest-end 13" configuration so I didn't lose any performance in the transition, and haven't noticed any discernible difference in "real world" use.