Mail.app has sucked ever since 10.6.8
Mail.app in Snow Leopard 10.6.8 was the best e-mail app I've ever used.
So of course in Lion Apple had to go and mess it all up. It was so slow as to be unusable. Mountain Lion addressed the speed issues somewhat but I still see LOTS of annoying behavior (can't click-drag to select messages anymore - WTF; click on messages and have them get marked read, only to shortly afterwards reappear as being unread; delete large groups of messages and Erase all Trash folders yet the messages never got moved to the Trash; Erase Deleted Messages/In All Accounts would take less than a minute in Snow Leopard yet take several minutes in Mountain Lion, etc.).
New releases are supposed to be better, not a backwards step.
(I tried MailMate but it crashed on my personal e-mail account and seemed to be too single-threaded to handle my other accounts where at least it didn't crash.)
Mail.app in Snow Leopard 10.6.8 was the best e-mail app I've ever used.
So of course in Lion Apple had to go and mess it all up. It was so slow as to be unusable. Mountain Lion addressed the speed issues somewhat but I still see LOTS of annoying behavior (can't click-drag to select messages anymore - WTF; click on messages and have them get marked read, only to shortly afterwards reappear as being unread; delete large groups of messages and Erase all Trash folders yet the messages never got moved to the Trash; Erase Deleted Messages/In All Accounts would take less than a minute in Snow Leopard yet take several minutes in Mountain Lion, etc.).
New releases are supposed to be better, not a backwards step.
(I tried MailMate but it crashed on my personal e-mail account and seemed to be too single-threaded to handle my other accounts where at least it didn't crash.)