Locally , there are a number of these engines.
The worst offender -which adds to vibration -is the prop-
The worst prop type for vibration -is a low pitch Zinger.
Also - some Zingers -especially notable, are the std types -not the Pro , which often have a flat grain pattern-- sometimes on one blade which allows a lot of flex-
This causes vibes and low performance.
The best props for low vibes -are the beechwood props -and glass props -
So Bambula/ Menz- Mejzlic etc are very good.
Also the thicker 12 " pitch props -cut down from larger props run smoother - as they are stiffer.
As for any of these engines being inherant vibrators - I simply have not seen that. So far -we always found a reason for vibration -and it was typically a prop- not always but now the first change out a vibration problem.