I did just that and found the improvement to be significant and enjoyable. Better micro dynamics (to me, all the peripheral sounds that give a better sense of realism) and greater presence and bloom. With the Zenith, the music did not sound as thin as it did before at the same volume. I stick with moderate volumes.
I have, however, made many changes and improvements since the Zenith so I may not remember the exact details of the Zenith's contributions, but I do remember being very pleased with it when installed.