Spiderman is one of the last good (and full featured) pins from Stern before they went into 3 years of cost cutting mode.
I would be going the Spiderman on the basis it more than likely won't be run again, and it will hold its value in the medium term.
5-6 tops for the SM, by the way.
8950 for the blue Avengers LE which apparently drops to 6400 two weeks after you take it out of the box.