Yarn consistency tends to vary depending on my current level of concentration, but I can manage to make a relatively even sock yarn (I find it trickier to make it at a 4-ply equivalent than as a double-knit, though both are possible).
I've given my handspun to total beginner knitters before and it worked fine! (Though that admittedly was for a chunkier yarn).
I've not knitted that much with nylon mixes. With pure wool, I tend to find the socks need darning after a year or so even if only worn occasionally indoors.
But they are fun! Just keep a supply of scraps for mending.

For info - see the various "Knitting" sets at http://www.flickr.com/photos/tictactoepony/collections/72157602825442173/ if you wish to see examples of things I have spun and made from it.