I had the chance to compare the i3 to the Sony IER-Z1R over the weekend. Quick thoughts on both, streaming Tidal via an iPhone XR into an iFi xDSD. Stock tips and cable on the Z1R, and Azla Sedna tips and FiiO LC-3.5D silver cable on the i3. Firstly, I was pretty surprised by how close they sounded, both in terms of their tonality and presentation. There's greater treble presence on the Z1R, although the difference is not tremendous to my ears. As to be expected, perhaps, there's just
more of everything on the Z1R: soundstage, transparency, clarity, etc. Here's the thing though: swapping back and forth, what struck me most was how similarly enjoyable I found both units, and how well the i3 held up. It's hard to put a number to it, but switching back to the i3 each time, I didn't find myself feeling as though I was sacrificing all too much technically. All this to say, at ~$150, the i3 are a ridiculous value.