I agree. They should have come solid from the factory like the next gen.RSFB feedback::
Just put in the Bimmerworld solid aluminium subframe mounts. Rear end is rock solid. I can't feel any added NVH at all.
They cost less than $300, though the install cost IS higher unless you have an extensive shop at home as they had to be pressed in. Not something you can easily do in your garage IMO.
After driving cars and mine with various setups, I dunno why anyone would bother with anything other than 1. Stock, 2. White line inserts, or 3. Solid aluminium.
Anything else is just an expensive compromise.