Indeed that sucks balls
How did that happen Robbie?
Did it occur at high revs or just normal driving?
I think that further investigation why it flew went off is warranted before you go ahead and acquire another harmonic balancer.
Ross Tuffbond balancers (metal jacket types) are renowned for spitting belts.
Also, there plenty of members that run standard / OEM harmonic balancer Robbie and don't throw any belts - food for thought.