I bought Tier 2 when it was available and moved most of our books from Draft2Digital or Smashwords to PublishDrive (save the percentage they were charging). I left Amazon as is and you can easily choose which stores PublishDrive pushes too.

Over the past two years, it has been great, and the software keeps getting better. The recent UI uplift is nice too. We get paid on time and the reporting is as good as can be expected (they are at the mercy of the distributors--as are Smashwords and D2D)

WHO IS THIS FOR?
If you already make money from book sales, it's a no brainer. A lifetime offer where you keep 100% of the royalties makes it easy to calculate when you start saving money. If you are currently using Smashwords or D2D, there are no on-going costs, but they take a cut of the royalties.

We publish a monthly magazine as well as many books on learning Japanese. As a result, we have a ton of ebooks to sell. PublishDrive made sense to us.

But! If you are just starting out and you don't know if your book will sell even a single copy, maybe Draft2Digital would be better. There is no cost until there is a sale.

I haven't had a bad experience with customer service, although I haven't had to use it much. But questions were answered in a timely manner, and I've experienced no major hiccups despite moving dozens of eBooks from other services over the years.

So, PublishDrive--come back! I'd love to buy a few more. :)