Note: This answer is relevant only if your goal is to do pdf reports.
We were having same troubles using crystal or telerik reports and came to conclusion that using html -> pdf conversion approach is just most productive.
wkhtmltopdf is great for it. You can basically assemble html report in (asp.net razor, java...), send it to wkthtmltopdf console application and get back pdf.
We went little bit further with this approach and implemented jsreport reporting server. It additionally includes html report designer, JSON REST API, javascript templating engines interpreter and also maintains report templates for you.