I use Maxthon and FireFox. Maxthon is really not a browser, it uses MS IE as its core. It is however easily the best thing to date for me. I love the features. Maxthon hasn't simply just prettied up MS IE they have improved it vastly. I would recommend it. I have it installed on ally my systems.
I have removed all links to MS IE on ally my systems home and office. It's stilled installed but the users cannot find a icon to start it, instead they have Maxthon and/or FireFox.
FireFox is great, fast, but not as feature rich. Opera is another browser I have loaded. I use it rarely as a number of sites don't load well in it, for whatever reason, not always the browsers fault. Opera is supposed to be more secure than all the above, but there is a trade off, and I am webaware enough I think that I prefer a feature rich browser that protects from, or warns me of, the main assaults from the www.
I have used firefox for over a year plus, but I did not use it for the protection of viruses, or spam. I used it because it was new at the time. I agree it is faster than IE, I only use IE for Windows Update Site and a few other sites.
Right now, I do not use Firefox very much at all since I downloaded a new Browser called MYIE2 which is now called Maxthon. I have been using this browser for quite some time now, it is designed somewhat like Internet Explorer, I use this one all the time. I also,use Netscape. I have never had a hijacked or anything else with any of my browsers including IE6. Maxthon also, has different tools that IE does not have. Try it out.