Funny, I was thinking just the opposite.
$15 is WAY too much to spend on a 4" figure; die cast or not.
I hear ya Ruiner, but I guess I just regard these as something more than a simple 4" figure. They strike me more as nice display pieces, and the addition of a display case alone seems to justify a little extra cost. Plus, metal is obviously a lot more durable than plastic. I dunno, a metal figure/statue in a nice display case seems like a good value for $15, but I admit it's hard to make a judgement until I actually see the thing in person.
On another subject, I dig your handle. Was that inspired by the Nine Inch Nails song?
-Matt