Having some very 'public' email addresses, I receive hundreds of junks per day. But, I NEVER want to risk a false positive marking of a valid Mail -- so my technique is based on specific rules, rather than a flexible, uncertain 'score' from spamassasin (or similar).

And furthermore, my emails are private - I keep them, and they're taken OFF THE INTERNET multiple times per day. With the kinds of search tools you can use in desktop Thunderbird, it remains my client of choice. I only only do webmail in a phone when I'm on the road and traveling "light".