This pen drives me absolutely batty. It is really cool looking and I want to like it, but there are too many little things that bother me that keep me from using this pen very much. The rubber grip looks nice and squishy in the photo, but in reality, it is rather firm and has a slick, almost plastic-like feel. It was uncomfortable to write with since there was very little give in the grip. The retractable button was also a huge annoyance. It functions just fine, but there is little to no click feedback when pressing the button. It's like you are just depressing a spring and it never clicks into place, despite the fact it is working properly.
All in all, I was pretty disappointed with the Uni-Ball Jetstream Premier. The Jetstream Sport gives a better performance at a much better price.