Behind Xtra-PC is the power of Linux, Debian Sid (Casper?) to be exact. That knowledge would be intimidating to that MS-Windows user. After all, Linux is for computer geeks and hackers and is way to complicated for ordinary folks to install, configure and use.
By touting its virtues and barely mentioning its underpinnings, Xtra-PC will entice the unwary and deliver on its promise. Linux users know this, so Xtra-PC may seem to them as a waste of money. They already know how to install, configure and use Linux, but they are not the market for this device, their grandparents are.
I purchased the $ 25 version which comes on an 8GB thumb drive. The same software is also available in 16GB, 64GB and 128GB versions. Bigger drives provide more storage space with possibly, maybe faster memory chips on them.
The 8GB drive is partitioned as follows:
Partition 1: 47MB fat32
Here, you will find the autorun.inf file and a README.TXT instruction users to read the docs from the website and remind them that Xtra-PC must be accessed from the system startup, not from MS-Windows.
Partition 2: 5.50GB ext4
This is where Debian lives. There's not too much room to install additional software, but the most commonly used software is already installed. Also, the most current version of Debian (jesse.sid) is not installed but not really needed since things just work out of the box.
Partition 5: 1.82GB swap
Since this is targeted to old or low-end machines, some swap is probably necessary.
Installation and setup is quick and non-technical and it works as advertised. As a Linux user, you might want to purchase the $25 device to have handy after installing a few repair tools.
There have been several attempts to offer MS-Windows work-alike Linux distros. Xtra-PC appears to be the closest yet.
Since it is intended for low-resource machines, I did disable the whoopsie process, a Canonical error reporting mechanism not likely to be useful to granny.
There are some tips to optimize Debian running on a flash drive here.
The special scripts that Xtra-PC uses are located in /opt/xtra-pc.
Since it is intended to run on older hardware, it might be useful for Linux to identify itself to the machine as "Windows XP". YMMV.