The one thing I didn't see mentioned here is.....

If you have a small(ish) fire on startup (hot start), abort the startup procedure and hit it with CO2, you CAN (after checking everything over carefully) perform another start and go fly if everything is okay.

However, if you hit your engine with Halon, Halotron, or any other liquid or chemical extinguisher, YOU ARE DONE. You have to send the engine and components in for service, and most likely strip the airplane down and clean everything.

So, which route would you rather take?

Just food for thought.

Brg,
Mark