I'm also using a CS4 aug, much to the bafflement of the guild tanks. Not only does it work for interrupting cleric mobs it also allows me to hold aggro (along with Sting) should I need to tank anything for any length of time.
The only thing to be wary of is that if you're acting in a DPS role, meleeing with Panther and casting Sting willy-nilly you
will be tanking if the real tank's not paying 100% attention...
(Incidentally there's not much need for Enraging Blow any more - String is 3K raw hate assuming it lands for full. Assuming 4 procs a minute of EB, you're only looking at as much aggro as you get from one Sting!
)