Welding Tips and Tricks

I've been playing around in our fabrication shop with our automated PTA machine and torches. I love the precision and accuracy of the weld beads.

Very nice. Is it used for any thing else other than hardfacing teeth?

How long do the tips/nozzles hold up?
Is this the type of plasma welding where the work piece is part of the circuit or the type where the arc is contained in the torch?
Looks shiny,I want one!