Does your yarn have any recommentations for needle size on it? I just saw an interesting article in Kint 'N Style Dec. "07 issue page 34, in which they makes a suggestion that you "fold the yarn in half and lay this double strand across a needle gauge. The hole that covers both strands completely is a good starting point for the size needle to use". I've never done this, but thought it seemed like a good idea.
I love Skacel circular needles myself but they are metallic and many people say they are too slippery. Lots of people love the bamboo. You need a smaller length like 16".