The only thing that keeps me from using Safari is the way it handles links that are programmed to launch new windows. I've been on tabbed browsers for years, and hate secondary browser windows. If Safari ever adds an option to open those new windows as new tabs instead, I'll switch to it. Until then, Firefox all the way.
I understand that I can manually tell Safari to open a link in a new tab. Not good enough. It's the surprise new windows that bother me most. If I don't know that a link wants to open in a new window, I'm not going to know to do it manually. And I certainly don't want to get into the habit of opening every link in a new tab.
Also, I'm aware of SafariStand. No thanks. Tied it once, and couldn't get it to work. The installation procedure is very un-Mac like. I also get nervous about messing with an app that is so tightly integrated with the OS.