Got my upper engine mounts changed today for the PowerFlex ones. I did the upper engine mount, and the torque mount. The car feels absolutely mint now, like a difference I never expected.
There are zero knocks or bangs, the gear change is absolutely perfect, and the engine seems to rev much better than it did before.
As for vibration - YES, there is noticeably more vibration. Mainly at idle, but I noticed when driving at 30, the middle mirior was slightly distorted from the vibration. Now, I assume they will bed in a little bit, they're fresh out the packet, but, IMO, the added vibration is absolutely 100% worth the better driving experience.
One thing I would say is though, it was an absolute pig of a job. The upper torque arm was very easy, the upper engine mount bush insert was an absolute *******. It took 2 of us (1 mechanic and me) about an hour or so to get both fitted. We had a jack under the engine to take the weight, and took every bit of effort to push the engine back and fourth to wiggle the mount out, getting it back in was even harder. We ended up loosening off the air-con pipes just to give us an extra few mm of wiggle room.