I've only done socks once and it was kind of a pain but very doable once I figured out the hoop. My Janome 350e has a 2" free arm hoop, and it has a little "blocking plate" that sticks up and keeps the rest of the cuff out of the way. It works well for embroidering something small on onesies too. I also have those hoop guard things too for the bigger hoops but I don't really care for them, I have better luck just pinning stuff out of the way.
Cari