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Any difference in new standard engine mounts will depend entirely on the state of your existing ones. I'm not aware of VW revisions to the Mk5 GTI mounts.
You probably already realise that oem mounts are designed for the mass market which comprises of a majority of drivers (and fussy passengers!) who primarily want quiet comfort. The compromise in providing that is a less rigid drivetrain and quieter cabin.
So that loads/stresses are more evenly distributed it's considered best practice to change all three mounts. However, it's the lower mount which is the one which directly helps get the power down.
As to vibrations (very minimal 'buzz' and only on cold startup) and noise, it's really very subjective. Stokeballoon didn't like the
Grrrrr sounds and Mat, Hurdy, and I love it.
Ideally you need a ride in a car with aftermarket engine mounts.
Hope This Helps