If you haven't seen Gartner's report titled Quantifying the Value of Microsoft's Desktop Optimization Pack then you might be interested in giving it a read.  Since SoftGrid/App-V is part of the Microsoft Desktop Optimization Pack (MDOP) and to get MDOP you need Software Assurance (SA), this information should help you assign a dollar value to the various components that make up the MDOP package.

Organizations that buy Software Assurance on Windows clients have the opportunity to subscribe to Microsoft's Desktop Optimization Pack. It is essential to quantify the value of the components of MDOP when determining whether investments in MDOP and SA will be justified.

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