No it's not. std::endl draws a newline and flushes the output buffer. I would say it's best to use '\n' instead of std::endl if you're drawing newlines frequently. It might get a little slow.
I thought, std::endl would be a OS dependent constant for a linebreak, so one doesn't need to fiddle around with "\r\n", "\r" and "\n". So i've learned another thing, thanks :-)