I just picked up the new Riffe dive knife at MBT. It has a locking clip and a safety!! Fritz ordered it for me and I think he got a few extra for the display case... Now if this weather will just cooperate so I can go skull a mean 'ol AJ.
The Riffe Knife doesn't have a "line cutter" persay, but it is sharp enough to cut through just about anything.This knifeis specifically designed for killing fish. I usually carry a Z-knife for line cutting purposes. It looks like a gut hook. It has two finger holes, and a hook with a razor blade in it. They are cheap (around $10-$15), compact, and efficient for cutting line.
I've got one of those things, and it kills fish really well. On my list of fish to do in with it are Red Snapper, Cobia, Triggerfish, and Hammerhead. I'm sure you'll enjoy doing in some fish on your own list.
i have that knife and i love it. the first time i used it i was shocked it went in like a hot knife in butter. the only bad thing is wheni pull it out i was in a green cloud instanly if you no what i meen and the cudas were like hey whats going on over there.