As a programmer I don't care which browser is more standards compliant. I need to know what works. On this site, I have had to only make one adjustment for Opera for the cascading tutorial menu.

@media not dummy
{
  #wspt li:hover li:hover ul, #wspt li.zgHover li.zgHover ul
  {
    left : 149px;
  }
}

The @media not dummy is an error for everybody but Opera and they quit processing the stylesheet. The trick here is to make the Opera styling the very last part of the stylesheet. Browsers reset when they start another stylesheet so this can be in any stylesheet. Luckily Opera 9.0 renders the same as Opera 8.x.