Titanium won't shatter and slowly seep undesirable elements into your tank.
Oh, and the cord melting and sending a charge through corals and fish stressing them out I could've done without. Course that's not always the case, just IME with glass heaters.
I'd have to call that one a draw. I've had Titanium heaters short our where the cord enters the heater. No mater which you use you need to check them from time to time.
What about plastic heaters? Greg Hiller suggested titanium and plastic over glass and I thought he said plastic was better due to the possibility of titanium being a metal in a SW tank and could leach...