Mail.app alternatives (gnumail, mutt and so on)

I want to change the email client from mail.app to something that I like more. No clue which to go for, so I have to try the various options on the list

Mutt is great, when you don't mid using vim .. it is actually very effective too - however I think to make that work, to bypass the firewalls etc it may take some effort again.
Gnumail isn't bad, maybe my 2nd option, if it runs on 10.4.
Sweetmail looks funny.
Thunderbird felt cheap, and the integration with addressbook was poor, I used it a year ago, and didn't like it - M tried it in January, and it hasn't improved its usability. However it still bypasses all the MS provided options. For some reasons I do want to not have nay Mircosoft products on my Mac at all, so there is no reason to go to Entourage -- call it not accepting the end user licence (when there is the site licenced version), and if that is not enough, then the unwillingness to have zombies running on my system. (The only times I had zombie problems was when I had MS office installed - OpenOffice may be ugly, but no zombies).

Mutt seems so far the best. Even though mail.app's search is not a joke any more, it still lacks options I need, does not allow me to control everything, and amazingly the most satisfactory experience of all email clients goes to the one with least gui. So it's all in you key strokes which ever will be the fastest and most versatile to use.

There doesn't really feel to be anything out there that I would like more. At least of any unix, open source or other free versions. Time to create your own, or accept what is out there. Let's see what I decide within a few weeks - probably it will be mutt + vim.