I haven't but am going to check it out and research it a bit.
I've been trying to utilize Lulu and have used them for one small project in the past. I'm having issues formatting to the file sizes they use for my current project. The graphics in the new book are coming out all distorted too, which is highly frustrated. (something that wasn't an issue last time)
I'm going to look into Create Space though, thanks for the heads up.