I've never experienced db's problems, and there are a couple of things I don't like about Opera, but it's the one I use the most. I use it for all my email now, I use its built-in IRC client, and I've even tried its new built-in bittorrent client.
I like the new Firefox, but I still prefer Opera. There are lots of little things I miss. Like for example, in Opera if I accidentally close a tab, I can unclose it with one click. A tiny thing, but really convenient at times. There are lots of these mini features in Opera that other browsers don't have.