As a printer, Stylus SX100 worked out of box. In spite of being cheap, its print quality is very good. Epson printers are also known for their cheap ink cartridges. The only drawback is the slow print speed.
The scanner, on the other hand, is not recognised by my operating system. There is a chance that there are linux drivers for the scanner somewhere, but it's a tough call. A workaround is using it inside virtual Windows - and then the scan quality proves to be good, especially for such a cheap machine.
The photocopy function works fine (you don't even need to connect it to a computer), and it's of good quality as well.
Overall it would be a very good choice if the scanner was supported.
Hint: In case this machine is not recognised by your distribution, it's good to know that the printer driver is provided by the
guttenprint project.