Self-publish or use Createspace?

Numbers, numbers.

Createspace gives you the flexibility to publish a small number.

Self-publishing may well let you have a lower cost.

What's the convenience of Createspace worth to you?

Createspace costs you nothing. You get instant Amazon marketing.
And Amazon walks you though every step. You can also buy your own copies of your book in any quantity, for a few dollars.

I've self published a book. It's beautiful. I have 4,000 copies left.
I have 4 books on Amazon published on Createspace. They print one copy at a time, as people order.

It's a no-brainer.

using Createspace is self-publishing!

I have five books on Amazon that I've self published using CreateSpace. They are great and you can purchase copies for your own personal sales for less cost per copy than any other company that I know of unless you purchase thousands of copies at one time which I do not recommend. And the best part is, your cost per copy is the same if you purchase one copy or a million. Shipping costs are pretty high unless you purchase at least 10 copies or more to make the shipping per book more reasonable. ISBNs are $200 for one and $250 for a block of ten. Since I knew I was going to publish more than one book, it made sense to purchase the block of ten and bring the cost down to $50 per book for five books. CreateSpace will give you an ISBN but they become the publisher and have control over your book as where you can sell it. I prefer to buy my own ISBNs and be my own publisher. I have a graphic designer in Tennessee who designs my book covers from scratch for $200-$250 per cover. The main thing that I can't stress enough is that your book will compete against millions of other books and will likely never be seen unless you do some kind of promotion like advertising, blogging, adwords, etc.

I have two books on Amazon, done using Createspace. Createspace IS self publishing. It's been a few years but I paid the $40 for the Pro version or whatever they called it. I got my books for less, and it paid for itself with about 10 to 12 books sold.

Before I did my first book I checked with a local printer on what they would charge. It was almost double what CreateSpace charged AND they required a minimum of 100 copies. I showed the numbers to the printer and he was shocked!

CreateSpace is super easy, but as other posters say, the real issue is marketing. So, use CS, get a GREAT cover done and have at it.