I took a coupon to Michael's last weekend and I bought a set of #8 29-inch circular bamboo needles. The straight bamboos I have are #8 and I had already started a project on them, so after much internal debate I decided to stick with that size. (Besides, all the yarn in my stash is the same brand/type and all recommend #8 on the label.)
I transferred my work over to the circular needles last night (starting with the fourth row) and I really love working with them. It isn't that much different than using straights, yet somehow it is so much better!
Here is a picture of my work so far.
(The three balls used to be different sizes and I wanted a picture of them all together. The largest is being re-rolled into a center pull ball, the second largest is being used for my WIP and the smallest one is just sitting there for reference.
Thanks again for all your advice and encouragement. I can see why some people use circular needles exclusively and I have a feeling I'm going to become one of them.