A recent news item discussing the new version of Opera seemed to indicate it could open fewer pages than could Firefox, but outside of that, had some really good features.
The problem with browsers based on the IE model is twofold. First, the IE engine is part of the Windows operating system, and second, that they use activeX controls (a favourite tool of malicious coders). Neither Opera nor FF make use of these controls, and are completely independent of the OS.
While NO browser is completely secure, either would therefore be better than other alternatives. It has been my experience with FF that there are very few pages it cannot handle (mostly MS sites), and there is an extension that will allow you to open a recalcitrant page in IE should it be necessary.
In addition, the folks at Mozilla seem prepared to patch identified security problems much faster than MS (that is not saying much) or the people responsible for Opera; in some cases, Mozilla's turnaround time has been less than a week (I remember one that took two working days). The ability to have your browser patched quickly is certainly a prime element in its overall security.
Lastly, whenever you deal with a IE clone, it seems to me you cannot be assured that MS security patches are compatible with them, and that whatever these clones add to the IE engine is either well-coded or itself secure and doesn't add additional secuity holes to your computer.
Edited by jgweed, 25 April 2005 - 03:53 PM.