Sure you could use dpns instead, though I use 24" ones for hats. I CO to another one, usually the next size up, and then join and knit the first round with the size I intend to use. The cuff is still too small, so I use a variation of ML - Modified Magic Loop
- for a few more rows. I usually inc a few stitches, and then the 24" works fine until a few decs where I switch back to the MML till I have to use a real ML.
You can also knit it on 2 circs and the length doesn't matter, though you wouldn't want a real long one.