which distro + DE are you using these days on the Pinebook Pro?

[moonwalkers]

why did you choose Debian Sid?

I'm asking because I'm after a distro and DE combo that provides the greatest performance and stability on the Pinebook Pro. (I should have pointed out in the opening post.)

Because that is the right distro for me :-) - I can be as hands-on or hands-off with it as I want. That and I kinda appreciate it's libre leanings, even if it can make it hard sometimes to get certain hardware to work or deal with certain proprietary formats.

The performance will primarily depend on:

• your kernel
  
• accelerated drivers
  
• your choice of software
  

The kernel you can always build and fine-tune yourself, and unless you're running something like Arch BTW (sorry), you distro kernel will probably always lag behind the upstream at least a little bit. Accelerated drivers - similar deal, though at least based on my Debian experience making the piece of software you build into a proper package that is handled cleanly by your package manager seems a bit easier with Linux kernel than with something like Mesa.
But by far the biggest effect on your performance will have your choice of software - how much of it you run, and what do you choose for each piece of functionality. E.g., as KC9UDX already mentioned, XFCE would be more lightweight than KDE Plasma or GNOME, LXQt probably would be lighter yet, but then you can just use simple Openbox or one of the tiling window managers like AwesomeWM.
Point is, distros do differ in how quickly they take up updated packages, but the main difference is how things are done - both in terms of OS management and in terms of community. Everything else is up to how you configure your system - you don't have to stick to out of the box experience.