NPRD-2011 has multiple listings for inserts but I do not which, if any, refer to Helicoils. There are both coil and solid inserts with multiple manufacturers including Helicoil, Keensert, Powercoil, and E-Z-Lok (you could contact some of these companies and request for reliability data). The Helicoil catalog lists MS standards and perhaps you can search NPRD-2011 by MS number.

Personally I believe the best way to determine reliability of threaded inserts is to perform a load.stress anslysis then calculate reliability usin the stress/strength interference method. Regardless of generic listings it is the design and application that yield reliability (or lack of reliability).