I would show IE6 visitors a site with limited css (Progressive Enhancement) but would also like them to gently show a header informing them they can/should upgrade to a modern browser. There are initiatives out there, like ie6nomore, who do just that. But the list of modern browsers and the headertext is hardcoded.
My site is localised, so I rather have a link to an external website, that autodetects their browser language, and informs them of modern browsers in their own langauge.
That way my 'advice' will always be up to date and fully localized.