Better ways to check for project upgrade rather than relying solely on UpgradeProject_CheckOnly

Am using VS 2010 SP SDK and VS2010 compilers to build a VSIP package. The implementation uses IVsProjectUpgradeViaFactory->UpgradeProject_CheckOnly method to confirm if a project needs an upgrade. This function  returns pUpgradeRequired as true for a solution containing a website and a C# project created in VS2010. Please see  http://social.msdn.microsoft.com/Forums/en-US/8f133c25-06c6-45d0-80c1-bb25d0f85e44/unexpected-pupgraderequired-value-returned-for-a-vs-2010-solution-with-website-project?forum=vsx.

Would want to know if I can use any other output param or a function  in conjunction with pUpgradeRequired to determine if a project actually needs an upgrade. 

Thanks,

Vinita

Vinita