I have two. Purchased both at Best Buy to decide which I liked better and ended up keeping both.
One is a Targus (I believe). Shorter and slimmer. Easier to use as a stylus. The other is a "Rocket Fish." It's a re-branded version of something (maybe Boxwave?) for Best Buy. Better pen in that it's longer and thicker but not as good as a stylus.
Each is acceptable. Each has a rubber ball (rather than foam) style stylus.
However, I've since acquired an iFaraday stylus that uses conductive fabric over foam. It is so much better than either combo pen/stylus that I abandoned my desire to have only one implement and I carry both. Now if iFaraday had a combo it would be perfect.