Dear Ludek,
Yes, we will use CrystalReportViewer1.ReportSource = <the report object> in session as our primary solution. However, we still concern about the server workload and performance when using the session method. Once the server is overloaded, we will apply for the second choice of "cr.exporttohttpresponse(exportformattype.crystalreport,response,true,report_name)" solution. Users can then using the Crystal Report Viewer to open the exported RPT file at client side. That's why we study for it.
Best Regards
David Lau