It really comes down to the super easy Amazon integration. CreateSpace is owned by Amazon. You update in CreateSpace, Amazon pretty much instantly updates, and life is golden.
For those used to picking up paperbacks at the local supermarket, none of these systems have those "ideal sized books" for print on demand. It's just the way the printing companies are set up. They aren't going to be the little in-hand novels you're used to. They're going to be a larger size. It's sort of an "emotional" hurdle to get over.
Once you have accepted that, then I really do like CreateSpace. They've optimized their screens over the years - at this point it is very easy to work on books there. I have over two hundred paperback books in CreateSpace's system. I can load a new book up into there in about ten minutes flat. Load in the PDF of the innards, load in the PDF of the cover, and add in the description details. Ask for the review.
A day later the CreateSpace team lets you know the book looks all right. You hit approve and it's live!
It's nice to have their eyeballs glancing at the work and at least doing a sanity check. Then a few days later the actual final book shows up in your hands! Instant gratification!
I use this to create review copies for friends and family members. I print one and hand it to someone. They give me feedback, I make changes, load up a new PDF and print out another one. So it's very interactive, back-and-forth and people get to read and review an actual physical book which makes it easier on them.
I definitely recommend CreateSpace for all those reasons.
I'll note that this page used to have far more options on it. It is a bit scary how many self publishing companies have either folded or given up on self publishing because of the enormous power of Amazon / CreateSpace and Lulu. For example, CafePress did a HUGE push in the self publishing market for many, many years. As recently as July 2017 CafePress still had help pages posted to guide people through the self publishing process. But when I wrote them to check up on this option, they apologized and said they no longer allow book self publishing in their system.
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