Verant seems to be trying out a new tactic with set-drops. Each item in the set has a role to play, but isn't very good on its own. I can see the point, but don't think it'll work very well given they way players tend to think. Your average chracter will take the P.S.Mask and leave the Sash behind, getting a better belt elsewhere.
For visible items this changes a bit, because of the desire for matching sets (I understand this, as right now my warrior looks like a christmas tree with his green boots, red pants, blue arms, brown hat, and two centi WS).
Dunno. I'd keep this around for buying/selling. Other than that, I think it's something I'd bestow on a newbie in WFP, QH or BB.