First of all, why migrate from Crystal Reports to MS Reporting Services? Does it really bring in some considerable benefits? The short answer is yes, it does. SSRS proves to be much more suitable for scalable tasks, delivers better .NET integration as both technologies share the same manufacturer, Microsoft. SSRS is also free as long as you already have an SQL Server license. In order to determine whether your business is ready to migrate to SSRS from Crystal Reports, please refer to this article.

Single instance vs. multiple instances of SQL Server on a server