I had a 2006 P3 with Nitrous X. If the bow is one with Elite limbs I'd assume you would need A Nitrous cams for the short draw length. That's what I had. Never having shot a Mystic I can't compare the two, but expect some vibration with the P3. Nothing a little more mass weight and good stabilizer system can't cure, but it'll never be as vibration free as a parallel limbed bow. It's just the nature of the more traditional geometric design. The bow was a good shooter though and has decent length for finger shooting at shorter draw lengths.
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