Amazon's Createspace is the powerhouse of print on demand (POD). Everyone around the globe knows that now. Most authors are just coming to hear that there are other options out there, and some of them may actually be better. One of the most important things that other printers can offer, is a true distribution to retail stores.
Yes, Createspace says they have an Expanded Distribution option, although to get the full option you actually have to use one of their ISBNs, making them officially your publisher. Another aspect that may not be known, big stores like Barns & Noble won't purchase books from Createspace, because CS doesn't have a return policy. Due to space limitations, if a book isn't selling anymore, B&N need to send it back to make room for the incoming books.
Many authors are now coming to me and asking if I can get their books into the distribution. YES I can. I have actually been working with LightningSource, the publisher's side of IngramSpark for years now. Just today, I have had some reinforcement from a couple of my piers on why Createspace and Ingram should be utilized to expand your book's reach.
Visit my friend Sandra's site, where her guest blogger is another publisher who uses both, and offers her advice on which way to go if you really do want to make a choice between Createspace and Ingram. He true advice is actually to use both though.