If any Mac users are needing better email clients, I just made the switch this week. I was using Thunderbird and Apple Mail (one for personal, one for business). Apple Mail completely crapped out on me a few days ago and refused to download mail. It did the same thing in the Spring and didn't start working again for a week – so this time I just ditched it completely and decided to find new, more modern mail clients.
Postbox + SpamSieve
After looking at the recommendations, I decided to try Postbox. The migration was pretty much effortless. Postbox read my Apple Mail settings and I was up and running very quickly. There was a lot of clean up that was necessary – mostly because I'd been keeping a couple weeks of messages on the POP server that then became duplicates, but that's not Postbox's fault.
The biggest thing was getting spam protection up and running. I had to install the SpamSieve plug-in and then train it on what's good and what's bad as I went through all those duplicate message. That took quite a while, but the results are pretty good – better than Apple Mail or Thunderbird ever did – though I'm still having to be careful and continue to train it.
AirMail (w/ SpamSieve)
Then yesterday I migrated Thunderbird to AirMail. There were a lot of negative reviews on AirMail, so I was a bit nervous, but despite the bad reviews most of the reviews were positive, so I took the gamble. There's no 30 day trial like Postbox, so spending money on something with bad reviews felt a bit risky, but I didn't see any alternatives that seemed more promising. I also questioned myself because I've been with Thuderbird for YEARS and it generally works. But I just felt it was time for a change – mostly because I was sick of all the spam that gets through Thunderbird's spam filter.
The migration to Airmail was anything but easy. Airmail doesn't read settings of other programs, nor does it import old emails. However, setting up new accounts was pretty painless. It defaults to IMAP and I had to look up a few of the proper port settings for POP, but that was about the extent of the problems. It didn't make me enter passwords more than once, and it did guess some of the steps correctly – reducing what I had to enter.
The import issue was a pretty big problem until I figured out I could export the emails to a standard format, and then import them into a "local account" on AirMail. Then today I realized it doesn't even need to be all that divided – you can make it look like one big inbox by viewing "All Inboxes". But export/import was cumbersome since Thunderbird's "Save As" didn't all the emails. I had to find an add-on and use that for the export. THEN there were a bunch of emails (< 100 of the 13,000 or so that I imported) where the date/time didn't import correctly – they showed up as being from the time of the import – so I just deleted them.
Then once all that was done I realized that AirMail uses SpamSieve differently than Postbox. Rules on one don't seem to be used by the other. So, frustratingly, that meant that I had to retrain SpamSieve – something that I'm still working on.
Which Is Best?
So all this begs the question which of the four programs I've used is the best mail client?
Well, Apple Mail is clearly the worst – refusing to retrieve email for days on an end is a big no-no for a mail program. Almost anything is better than that.
I'd say Thunderbird is the old reliable one that works adequately, but it's spam filtering could be better. It almost never classified good stuff as spam, but a lot of spam gets through (then again I get a lot of spam – hundreds a day apparently).
Postbox is a revamped version of Thunderbird. It's feel is not so much modern as it is classic and competent. Basically it's Thunderbird with better spam filters. IMHO, that's a good thing and fits with the fact that I'm using it for business email.
AirMail is clearly more design-focused and "modern". It feels like like the new smart kid on the block who's a bit light on experience. It has integrations with things like Google Drive, Dropbox and CloudApp that I don't even understand the need for.
I'm not sure I'd say one is best. It sorta depends on where you're coming from and what you need. I can say so far I'm happy with Postbox for business emails and AirMail for personal – they seem well matched to the tasks.