I'm sorry but - have you owned the ones we're comparing? Not just used for 10 min in a store, but owned and used?
I've owned a 13 rMBP and dell xps 13 - and I gotta say, they're pretty comparable at this point. In fact, I preferred the xps with updated windows 10.
Right now I have my old 2015 15" retina and a Surface Book - and the MacBook Pro is the one that I'm going to sell.
I do audio recording and run some VMs..
The days of "windoze" and cheap plastic PCs are gone. Windows 10 is doing much more than Mac OS in my book at this point, thanks to the growing pains of windows 8 and early 10.
Haven't owned a Windows Dell laptop since 2007, when i switched over to Macbook Pro, when Apple went to Intel.
I haven't used a one with Windows 10, I'm going going off every version from Windows 3.0 DOS based to Windows 8 that I've used on desktops.(only due to work)
You telling me they have finally gotten it right after 20 years?
The Surface Book, if it works for you then awesome.
But for know I'm still going for OSX over Windows, as i can only go off my own previous experience and i find the Apple OS at this present time to be a better option.
This may change, and hopefully it does as apple needs a bit of a kick up the ass, or just clone Jobs.