I got some Kollage square circular needles, size 1, last month at Stitches West. They are supposed to be easier on your hands and help you knit more even stitches.
Unfortunately, I have no idea whether this is true in the long term, because I won't be using them long enough to find out. The cord on the size 1's is absurdly flimsy and next to impossible to use for magic loop, my preferred method of sock knitting. The join, too, is problematic, but I could get past it if they weren't otherwise so frustrating to use.
From their website's images, it appears that larger needles have more substantial cords. And I imagine that DPNs or regular straights may be better engineered. I am not swearing off on Kollage square needles for good - but this pair will be slipping to the dark, obscure bottom of my knitting supply bin.