I only recently got myself a used ThinkPad X220 that is now running PC-BSD. I tried a stock FreeBSD 10.2 first and could not get suspend/resume to work properly, so I tried PC-BSD, where suspend/resume works; then again the latest PC-BSD is based on FreeBSD 10.3, so a stock FreeBSD 10.3 might have worked as well; but now I am too lazy to re-install.

Otherwise the hardware is supported very nicely. Only scroll support for the trackpoint was a bit of a pain to get working.