This topic is a perpetual problem.  I've presented several workshops at our regional covering the topic of build or buy - issue to consider.  The handout is posted here:

http://orsa.uoregon.edu/ncura/IT_Workshop_Regional_2008.pdf

While it doesn't specifically address the available S2S vendors and the merits/problems with each of their systems, it may give you the tools to use to evaluate the problem.

FYI: University of Oregon has settled on Acrobat/PureEdge for the forseeable future. S2S solutions did not account for our internal development abilities or our institutional culture.

Steve Shapiro
Computer Services Manager
Office of Research Services and Administration
University of Oregon

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