gerelmx1986
Headphoneus Supremus
It's probably better and different though. It has more bass. So for some people, H3 has enough bass and they wouldn't get the Z5. I'm not sure if you are satisfied with H3's bass.
For me, there is not enough subbass. So Z5 might be a potential buy. But it's kind of too expensive for me.
I like the bass of the H3, i feel them at times bassy, and yes the Z5 price seems to be too high for me too, maybe another option would be the XBA-A3, tumored to have the same bass of H3 but widened soundstage and better mids & highs