Yup. I still don't see why everyone complains about current mail clients. Mail.app on OS X / iOS, Outlook on Windows, works for me.
To make me switch, you would have to show me why the new thing was so much better. Like how Google search results were always better than Yahoo! (IMHO, no objective measurements used) so I switched. You would also have to explain it in a sentence I could immediately understand, whereas all the recent clients I've ready about either (a) claim to make things better but don't tell/show me how before I get bored of the page, or (b) use manager speak that I can't understand or is vague and abstract promises to increase collaboration or something. Therefore I've given almost no attention to any recent attempt to change email.