The following is a debate that was held last night between Tanner Adams (affirmative) and AK Richardson (negative):
Tanner Adams Vs AK Richardson: Is Once Saved Always Saved True? EP 202
If anyone wants to know how pathetic the scriptural case for eternal security truly is, this is a "must-watch." Of course, I know other OSAS/Perseverance of the Saints apologists will just say "Tanner is KJV-only, so that is not representative of our best."
AK Richardson is a very good defender of the doctrine of baptism being necessary for salvation. On this, be sure to see my book-length treatment of the topic:
"Born of Water and of the Spirit": The Biblical Evidence for Baptismal Regeneration (for those who want a free PDF copy, drop me an email at ScripturalMormonismATgmailDOTcom)