I don't have lots of sock experience...but I've used tofutsies for one pair. I did not like knitting with the yarn, it seemed very splitty to me, but I've adored the finished items.
Cabletini socks
I made a pair of socks for my mom to wear with her ski boots from
Schoeller + Stahl Fortissima Colori Socka Color and I was so very pleased with it. Mainly, I needed to make the stitches as tight as possible since these guys would be seeing tons of work, and I was really pleased with the fabric they produced. Slightly scratchy (but I only wore them to try them on, washed them, and sent them to mom, so they might have softened) but it seemed to be a really really nice and durable sock. Also, loved, loved, loved, the striping.
Ski boot socks
I've also made two sets of little socklets out of Austermann Step yarn - lovely to knit with and my husband loves his pair. But I've found them to be a little saggy - but it could be because I didn't knit up past the ankle. However, the finished socks are really really nice to wear.