Well?
Personally I own each and every recording by Grace Jones ever made, every single:
studio album; CD, LP, 12" and 7" singles and all of her "Greatest Hits" collections.
But really, aren't "Greatest Hits" generally aimed at people whose curious of the selected singer?

I usually pick 'em up anyway, most of the times they contain new tracks and remixes of old classics.

So what do you think of "Greatest Hits" collections?