Yes, I have. Back in 2004 when it was 1stBooks.
I can't say that it was a bad experience, but I later found that it is only vanity publishing and will not allow you to sell to brick and mortar companies.
However, there is a package that will allow you to do that for a price.
My only problem I had was the idea that, after you buy your advertising package, it is up to YOU to follow up on those publicity releases and to talk the newspapers and Websites into printing the announcement of the book. Most don't care if you're not local. Sad.
If you have the money to buy the proper ad level and type of printing for your publication--still cheaper and easier than trying to get an agent and publisher--then you have a fair chance of sales.
As with all media, being a good writer or finding something that people like is still more important than how you get your stuff printed.
There are cheaper ways to publish though, especially if you only want a few copies. Lulu.com comes to mind. I even had a single copy of my book printed and bound at my local Staples for about $9.
As a fairly well known writer said to me, "The publishing industry is changing and you can't really get a publisher unless you can show them that you can sell books."
I know that sounds odd, but if you take your book, get a free e-book converter, and submit it to iTunes, Amazon, and other places that sell e-books, you can put together social media advertising and word of mouth for very little money and start making those sales. Then, when you can show a track record for selling, you can more easily find an agent and/or publisher.
I'm doing that with my next two books, "Mr. Monk and the Nitpicker" and "The Man Who Talked to Frogs". We'll see how that goes!
All the best to you!