Serious recommendation: go try the Raal SR1A's if you have a chance - not closed, but it's a neutral bass powerhouse with extraordinary treble speed and quality. For closed cans, I have to also advise against the Z1R. I've tried them on a variety of sources and I have to agree that they are just, well, weird. Lots of bass but comes across as kind of bloated and indecisive, treble is hot but quality isn't particularly good for the price. The one good combination I've tried them on is the THA-Z1ES which tames both the treble and bass and even at that, I feel that there are much better systems for the price. The IEM Z1R's I have not tried but it seems to be polarizing, some of the people I know like them, others are saying that it has the exact same problems at the can Z1R's. I actually have the XJE-MH2 which shares some of the Z1R's components, but the Just Ear team is apparently a completely different development group from the folks who built both Z1R's. The Ether C Flow is fairly neutral but I consider it the most technically accomplished fully closed design on the market. If you want to go fully closed the Focal elegia is also an option although I also found that one to be a little weird. IEM wise, the Tia Fourte sounds like something you'd enjoy. And for a pure travel option the Sensaphonics 2x-s is cheap, has incredible isolation and is a mostly straightforward, no-nonsense neutral tuning.