I had almost everything in Select for a 12-14 month period, just to see what happened. Now I'm in the process of transitioning out of KU. 7 titles still in, 41 out.
I use Smashwords to publish on B&N and Apple, dating back to the days when neither of those companies allowed Australians to publish direct with them. Direct on Google, Kobo, Amazon.
I use KDP print for paperbacks, as well as Lulu for author copies and hardbacks. (Lulu print in Australia. KDP don't.)
I use Author's Republic for audio. That was the only way I could publish on Audible from Australia, and I waited about eight years for someone, anyone, to show up and offer this Smashwords-style service.