CRM procurement: Presenting the case for CiviCRM
Take a look at the recent Idealware report comparing 'donor management systems' and CRMs. I do not believe it is totally accurate or fair to CiviCRM, but it is something like what you want. 

CiviCRM members are working on a side-by-side comparison of CiviCRM to 'competitor' platforms, which we hope to publish soon at the CiviCRM.org website.