fjtorres has given you a very good response already.
I use
Lightning Source. One of the big factors when I made this choice was having local (Australian) representation that I could deal with. The fact that they are part of Ingram, and so make your work available world-wide for very little cost (but it does cost a small fee per book every year), was also very important. My experience has been very good. They have been an excellent company to deal with and they produce excellent print results.
I cannot compare to Create Space, as I have never used that service, but I have had no reason to be disappointed with Lightning Source.