Returned to the stock mail apps all the time.
It really depend on how you use e-mail.
Reading description of the many e-mail apps in the store, it seems like they are made for someone who handle a lot of mails every day, so they have the feature to sort or prioritize incoming mails before you checked them. There's also feature to manage appointment invitations.
My use case, I only get occasional e-mail from newsletters or when doing online shopping.
Business mail stay in the desktop, and friends talk using instant messaging apps.
So in average, I have less than 1 mail per day. The Mail apps is enough to clean them up easily.