I don't have Zeus, and my good man @Deezel177 has already answered the bulk of your questions (thanks!) I'll just add the following in summation bcos I've spent only about 15 hours with Eos so far.1 - would it pair well with Zeus XR ? how does it sound and how does it affect Zeus ?
2 - is it a definite improvement over PW audio no5 ?
Eos - for note cleanness, separation, imaging, clarity and transparency. I like Eos for percussion and brass instruments.
No.5 - for note weight, timbre, naturalness and smoothness. I like No.5 for vocals, pianos, strings and guitars.