NewsForge's Robin Miller on Converting Outlook Users to Mozilla
Monday June 23rd, 2003
Poor performance is another one that's not currently a good argument... Mozilla Mail's performance with lots of email, both with local folders and IMAP, is nothing like as good as Outlook Express, IME.
Security, as you say, is a poor argument. After a long history of being crap, Microsoft's email clients are actually quite paranoid about what they will run these days. Jumping around going "look, look, our product is 110% secure" is not wise - one big security flaw and you're dead.
Rob gives 8 items in his list - 3 are the security thing, pop-up blocking and full screen windows are browser things, not email things (neither Outlook client or Mozilla mail news will run script in email), multiple email accounts - again, that feature is in both. Which leaves turning off GIF animation (not the most impressive feature ever) and the junk email filters.
The two points which are probably behind this thinking aren't stated: a) it's not Microsoft b) it's open source. Of course, your average Windows user probably wouldn't see those as compelling arguments.