Just got my X120e in the mail yesterday. Swapped out the hard drive with a 64GB SSD, added 2GB DDR3 RAM, and swapped the Fn and Ctrl key (BIOS option.
Minor note, mine shipped with BIOS 1.10 so I flashed to 1.11. Supposedly it improves video performance. I tried fullscreen 1080p Youtube video and it choked up a bit, but 720p works just fine.
As others have noted, the fan hums along pretty regularly but it is not too distracting.