You've tried other amps and ended with Pass, please discuss

So I'm genuinely curious about this, and I'd like your thoughts.

You: Are a current pass owner who has tried a number of other amps and stuck with Pass.

Please discuss your speakers, your pass and what other amps you feel your current set up bested.

I won't opine, but may ask questions to those who are not specific enough.
One thing I've heard a lot is the terms "refined." I don't know what this means, so if you can compare to other amps with more detail, would appreciate that.
Thanks!

Erik