Recently, I've been fiddling with getting it booting off USB to use as a wireless print server. It was working for a while, but after a power cycle, it stopped working. Apparently there are some driver issues with the Broadcom wireless card in there and booting off a Live USB drive (with a persistent partition).
While I was researching this, I came across a blog post titled How to revive your Dell Mini 9 failed Mini PCIe SSD disk, which implied that many of the SSDs that shipped with the earlier Minis had firmware issues. I figured I'd try the instructions out (basically creating a DOS boot disk with the utility), and lo and behold, the firmware on the drive updated.
I've got the Ubuntu installer running on it now . . . should be a lot faster than the thumb drive it was running off before, and hopefully easier to configure the wireless.