I have always developed in Internet Explorer and designed for Firefox. I also make sure that my site looks fine in Safari. However, there are a bunch of quirks and things that don't look too great in Opera, and I was wondering whether it is worth considering.
I know that Opera is just a small percentage of my visitors, but I would feel more comfortable knowing that things not displaying right are bugs in Opera and not bugs in my CSS that just so happen to not be noticable in IE or Firefox.
Is Opera known to display things a bit "off"?