Well, actually, it's been a good 2 weeks since I started using Opera. I just reformatted my HDD today, and while it fixed the Firefox problem, I actually found that I preferred Opera over FF. So now I'm using Opera permanently.
My only complaint? The toolbars are upsidedown.
With firefox, it went in this order:
Address Bar
Personal Toolbar
Tabs
With Opera, it goes:
Personal Toolbar
Tabs
Address Bar
I've fiddled as much as I can with the customization settings, but I can't seem to change the order that they appear in.
But otherwise, I think Opera is great.