I've been using...and buying...Opera since 1999. I am ok with paying for a superior product.
I've never understood the FF hoopla. It does not allow one to customise the look, (less a button or two...which are offered as extensions) adding removing toolbars, etc.
I don't know a single person running FF who is not using a metric ton of extensions.
I open Opera, I run it. It does everything OOTB that FF can only do with 15 extensions added on.
I don't get why people like FF so much. Opera, unfortunately, is a browser that one might have to put a little time into learning. It does have an IE skin though which should make it easier for the people who complain that they have no time to learn. Apparently they have the time to search the Mozilla site for hundreds of extensions though.
Opera hogs memory too. Not gigs, but enough that sometimes you have to reboot because it doesn't want to give the memory back. The memory problem is a problem with ALL browsers but I didn't know it was that bad in FF. I actually thought Opera was a worse memory hog. Go figure.
And I'm unclear as to the statement, "Opera needs an ad blocker." It has ad blockers. You can prevent pop-ups and you can block content on a page by page basis or tweak out your hosts file to suit you needs. I really hate that people, even people who are already using Opera, always fixate on ad blocker. RTFM already!
I use both FF and IE to test the html and css I write and to get to important sites like bank and credit card sites who, for whatever misguided reason, choose to believe that activeX is safe and needed. Otherwise, if I come across a site that refuses to build to standards, and not for IE, I just move on. Their crappy site is not important enough for me to open another browser.
I did try Opera 9.5 beta. Hated it, removed it, reinstalled it. They've screwed with the email formats,, jpw the wand works and some other things that piss me off. I'm unhappy with it at this point. I hope they do not drop the ball with this version.
So yeah, I love Opera, I don't understand why anyone would even want to use FF but I'm glad they're using FF over IE.