Roy, Yes I've been successful. Yes I've sold over 1000 copies of several titles actually. Yes I've had luck with 2.99 pricing (and 1.99 pricing for my fantasy novels). Yes I sell my books other places, too. I don't believe in putting all my eggs in one basket. It does not make sense for an Indie author to not utilize as many distribution outlets as possible.
But you also have to consider this - just because I've been successful is no guarantee other writers will be.
My successful books (I have over 17 books here) are in a sub-genre of romance. Women read that stuff by the truck load (trust me, I'm one of them). I also write fantasy and mystery. While my fantasy does so-so here, the mystery hasn't sold a single copy. However, over on Amazon - the mystery and fantasy novels both make okay sales. I also have non-fiction here and it sells well both here and on Amazon. My romantic novels don't sell as well on Amazon, even though I have two books in the top 20 erotica over there right now.
So not only is your success going to depend on genre (i.e. demand), but also how well you write and market what you write. I know other people who write romantic erotica whose books have not sold nearly as many copies mine. I also know fantasy authors whose fantasy novels sell better than mine. I know authors in all genres who haven't sold a single copy of anything.
There are a lot of different factors. If you're a serious, career-minded writer looking to get your work out there and to find an audience - ANY exposure is worth it. If you're a fly-by-night (a person who only has one book in them or who is under the impression that writers make big money and that writing a book is your ticket to financial freedom) it may not be worth it to you.
Not only that - but to make a liveable income as a writer (I don't care if you're Indie, small press, or published by one of the big six) you have to be prolific. Most of the successful Indie authors I know are very prolific and self disciplined and put out 2-4 books a year. If I depended on one book to carry me through - I'd have given up writing long ago. I put out 2-4 books a year to keep up with the demands of my readers. This year I've already released two. Last year I released one novel, two NF books and three novellas. So part of my success is actually the sheer volume of what I have available to my readers.
I get about 10x more purchases from Amazon Kindle, but I still think BN is worth paying attention to because they have a color screen and don't require ISBN 's-Kate