Using Classic Outlook on Windows for personal email, calendar, and contact management
Even with the super-fast double-click or the triple-click, this doesn't solve the bigger issue for me which is that I can't single-click an email. I tend to get a lot of emails that I can read through the one-line preview. I will often select them all and ctrl+enter to mark all as read. Can't do that with the new Outlook. Worthless to me.
I keep switching to the new outlook, and when I switch back I provide feedback when it asks. I'm sure that is directed straight to a person who immediately reads it and takes it very seriously.