I've heard a lot of good things about Bookbub, but honestly it's just out of my budget. I've tried a lot of things, and I've come to realize that I prefer the more long term book promotions.
With that being said, I've taken my books on a lot of online book tours... And I've been disappointed by several by the performance of several of them, with the exception of one.
Fire and Ice Book Tours is a good company to work with. On my tour, I had zero missed stops, compared to the daily missed tour stops I've experienced with other book touring companies. They also do a lot of social media promotion on your book, so you can expect to see it tweeted a lot at all different hours. They got me in within three weeks, compared to two months.
As for sales. I've been touring one of my older titles, and like I mentioned before, I've tried out several touring companies. I marked the book down to $.99 during all of the tours, and I didn't tour two companies at one time... I wanted to see what kind of results I'd have.
On my two week tour with Fire and Ice, I had close to a hundred sales... Without touring I only get a handful of sales on this particular book. On tour with other companies, I'd get an increase of ten to fifteen sales, give or take. A lot of take on the touring companies where the bloggers only posted the tour post half of the time.
So if you go the book touring route, try to find a company that will replace any missed stops. I would email in when a stop was missed and 90% of the time, I would never get a response back... And the tour post never went up. With this touring company, they actually update your schedule daily with a direct link to the post, which made it really easy to check it out, and I knew someone was actually monitoring whether or not the bloggers were posting.
Sorry for the long post... It's just been disheartening to work with so many online blog touring companies (and expensive) to have such disappointing customer service and results. For the future book tours I will take, I plan on sticking with the company above... Unless I just really hear great things about another company, and I decide to try them out, too.