I agree with most of your statements in this thread but you must realise that the toe arm is what is going to limit the movement in the side to side motion of the front of the trailing arm (left to right of the car when looking at it from the rear). The trailing arm bush is not designed to resist this motion, nor should it as it will bugger up the intended toe control of the toe arm with suspension bump and droop. Spherical bushings for this location have the pin completely free to slide, as it should be, and no-one complains about spooky rear toe with those designs.
Also OEM is good and when ordered from the US is practically the cheapest, or close enough. I got a pair of bushes and the tools to press them in and out for less than $190 and the tools made up more of the cost than the bushes.
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