At the time there were two versions; Linux with 4GB and 8GB solid state memory, or a Windows XP version with a HDD.
I worked out that I could buy the Linux version and an OEM XP CD for less than the cost of the XP version, and anyway who wanted spinning rust in a travel PC?
[I needed Windows to run software to manage a few hardware devices with Windows only software, including a TomTom satnav.]
Ran well for a couple or more years and did everything I needed whilst world travelling. However XP just kept getting more bloated and eventually choked on some updates because of lack of space. So it got stored away until I could re-Linux it. Still waiting. I doubt it would run W10 even if that was a free upgrade.
Recently (a year ago?) bought a small HP with W8.1, for much the same reasons. It works fine (especially after the SSD upgrade) and again does everything I need when on the road.
I can't decide if I should upgrade whilst it is still free - W10 sounds generally O.K.(ish) but the snooping, forcing, and general mistrust of MS weighs against this.
I do think that if MS get everyone onto W10 they will save so much on their support costs compared to supporting 4 separate versions (W7, W8, W8.1, W10) that they may well not need to charge. If they want to stay in business they need to keep their OS on the desktop and sell services on top. Of course, logic is not always their obvious strong point.