Just when I was thinking, that for my fishing needs I'd not need anything heavy, the builder of my rod told me of a time he was fishing bass and bluegill in a nearby lake, and a 12# catfish decided it was time to eat a surface bait! I've caught one 33" blue cat on a spinning rod from a kayak, and it was fun. I can't imagine it on a #5 fly rod.
If you manage to land it, it'll take you a while.
