We have some experience on this matter. For the first time if you used ODP.Net ver 8.17 plus Oracle Client 8.1.x to connect, there will be no significant errors we found. All sql statements run properly, but some complex sql failed after several executions.
We have change the ODP.Net to ver 9.2.0.2, and installed client 9.2 with OLE DB, and clean all previous version from production.
Check http://otn.oracle.com/software/tech/windows/odpnet/content.html.
By doing this , everything gone smooth..!!!
Regards,
Jody Ananda, MCAD, AWP
http://www.newmont.com