I know all about Mozilla, i've been doing this internet business since day one and I remember the original Mozilla in conceptual phases. The question isn't what I know about them, the point is, that I find them not very good. I'm very very picky on my products, and I demand configurability. I do not like companies telling me how I should use their programs, and I need deep configurability. Every Mozilla based browser i've ever seen doesn't even come CLOSE to the level of configurability that I have in Netcaptor or MyIE2.
As for mail, I use Outlook2003, and its perfect, the security holes in outlook express are not in OL2003, and its got the best spam filter i've seen in it, built-in. I've had at best, 2 spam mails get through to my main box this year so far and zero security intrusions via email that weren't blocked by either OL2003, or my AV/Firewall or ISP. I'd say thats pretty decent.
I know its hard for Mozilla fans to believe, but some of us actually use Microsoft based products by choice for one reason or another. Myself, I just need mad configuration of my products, without having to fuss with 100 other third party plugins to give me options I feel should be in the core product. But thats just my opinion.