Parabolics are supposed to be both quieter and slightly faster, but at our close-in distances, this probably doesn't make that much difference. I shoot 4" shields on mine, out of a Toelke Whip that's almost silent on release, and I don't hear any sound after release until it smacks the bag. Shields claim to be a little more stable, but I don't notice any difference whatsoever. I kinda think it comes down to a properly tuned arrow. If you're spun up you shouldn't notice any difference, so it's down to personal preference-in my experience anyway!