Opera or Firefox?

Just yesterday I found out that Opera Web Browser becomes another FREE browser. A big competitor to firefox.

I haven't used Opera myself before, but I've played with it and it's fantastic! It's probably the best (yes, better than firefox) but it was not free before. So I went with Firefox.

Hmm.. I'm now at the cross road. To Opera or not to Opera?
It's good and free, but it's not Open Source! Oh well, I may use a dual system in the mean time to test them side by side.

However, because Opera is not Open Source, it doesn't have heaps of great plug-ins (or extensions) like Firefox does. I love the foxytunes, adblock, StumbleUpon and Googlebar (which I just used to one-click blog this).