Any advice on reflinks... or XFS in general?

[psycho]

I was reading the (Gentoo website) article about the new ready-to-run Gentoo images and noticed that it gave (right at the bottom) the use of reflinks as a reason for the decision to go with XFS rather than ext4. Last time I looked at the performance comparisons between ext4 and XFS I decided to stick with ext4, but I'm curious about the possible advantages of XFS and whether reflinks are some kind of life-changing bonus that I ought to be enjoying. From a quick read through various explanations of reflinks they sound useful. Any advice on whether to use or avoid XFS?