I love my Harmony wood DPN for working socks in everything but dark yarns. For that I had to go back to light wood circulars.
just to add a suggestion to the great list of them you've already gotten: if the project allows (like a brim up hat) cast all of your stitches onto a straight needle, then knit them off onto your DPN one needle at a time. It's much easier than casting onto DPN. Join at the beginning of the next round like for a jogless stripe.