Firefox vs Opera

Which one is really the best?

Firefox has been shown to be slower and less secure than Opera, as well as not passing Acid2 or Acid3 web compliance tests.
Also a good portion of Firefox's addons are available as default features in Opera, such as the speed dial.

I switched from Opera to Firefox when O9.5 came out because I couldn't get AOL to work with it, but I think that's because I didn't enable activeX or something, lol.

anyway, there's a lot of false information out there, and I'm looking for the pure facts.
Which browser really is better, from a purely objective standpoint?

ActiveX is exclusive to internet explorer.

The acid tests are more e-penis than anything else, it's like criticising a mirror because it doesn't reflect 100% of the light that hits it. Not to mention, that safari and opera specifically design their browsers not to actually support the standards (and errors) contained in the acid tests, but rather to detect the acid tests themselves and display them "correctly".

Firefox 3 starts slower than opera 9.5 does on my computer, but once they're both up I don't notice any performance difference significant enough to care, which means the only last argument is extensions, and this is exactly why I love firefox. If there's something you want (or don't want), chances are it's possible and that somebody has already made an extension or explained how to accomplish it.

Spoiler for:

4chan 0.4.5.12
4chan 404 Defeater 0.4
4chan inline quote expander 0.2
Adblock Plus 1.0
Better Flickr 0.3
Better YouTube 0.4.3
BugMeNot 2.1
Bulk Image Downloader 1.40.0.0
ClearFileUploadFields 1.0
ColorZilla 1.9
CoLT 2.4.1
CSSViewer 1.0.3
CustomizeGoogle 0.76
DownloadHelper 3.5.1
DownThemAll! 1.0.4
Enrique B. and John S. 0.6.1
Extended Statusbar 1.5.3 [disabled]
FEBE 6.0.3 [disabled]
Firebug 1.2.1 [disabled]
Fission 1.0.3
Flashblock 1.5.7.1
Foxmarks Bookmark Synchronizer 2.6.0
Greasemonkey 0.8.20080609.0
IE Tab 1.5.20081203
Image Zoom 0.3.1
ImageShack right-click 0.3.6
InfoLister 0.10
Java Console 6.0.02
Java Console 6.0.03
Java Console 6.0.05
Locationbar² 1.0.3
MeasureIt 0.3.8
Menu Editor 1.2.6
MinimizeToTray 0.0.1.2006102615+
Nightly Tester Tools 2.0.2
Not4chan Extension 1.13
Organize Status Bar 0.6.2
QuickDrag 1.0.5
Sage 1.4.2
Save Image in Folder 1.2.2
Screen grab! 0.95
SearchStatus 1.27
Stylish 0.5.8
Tab Mix Plus 0.3.6.1.080416
Tab Scope 0.2.2.8
Tiny Menu 1.4.9
Titlebar Tweaks 1.8.0
TwitterFox 1.7.2
Web Developer 1.1.6

all I've noticed is that Opera manages to use less RAM on my computer than Firefox does, when the same tabs are open.

and what about the security issue?

I find that Opera keeps crashing! =/

Opera seems more safter tbh, coz when I use Firefox I end up finding loads of spyware.

I use Firefox coz of the addons and its fast the IE anyways and more stable, don'c crash.

posting from Opera.
it uses so much less RAM than firefox does, even with multiple tabs open and leaving it running for a while.

I'm not sure which is technically more secure, but if you're not a total moron, you don't have to worry about security. Firefox is secure, which is all that really matters, unless you're a middle aged man that doesn't know the difference between a png and an exe.

Also, I doubt you really need to nitpick so much about RAM, unless you only have 256 MBs of it, or if you're running tons of applications at once, which I doubt you are.

If running a browser is slowing your computer down, the browser is not the issue.

If running a browser is slowing your computer down, the browser is not the issue.

?____________________________________________________________________?

If running a browser is slowing your computer down, the browser is not the issue.

not saying the browser was slowing my computer down, but the extra resources for when I have a wiki up and a game going at once are quite useful.