CT
I intend to keep the Vellfire, so bought the genuine parts from Toyota.
The mileage is not the issue, it is mostly the age of the Vellfires that necessitate a change due to the rubber ageing.
Mine was hitting 13 years and low mileage - i suspect that all Alphards and Vellfires will have the same age related issues with engine mounts.
It's a very easy job and the improvement is remarkable.
Even if the rubber mounts look not worn, they will most certainly have sagged over time and brought the metal components closer together resulting in a loss of smoothness in the drive.
Remember, these vehicles are the Rolls Royce of the Toyota family, if they are not absolutely smooth, something somewhere needs addressing.