Cross-posting here with some ItsFit Fusion impressions and comparisons since I see them pop up in this thread a lot...
Okay, finally some Fusion impressions and comparisons now that I have had them for a couple days. Overall, highly impressed with the sound, especially respective of their price. They are also tied for the most comfortable universal IEMs I have ever owned (tied with Oriolus Percivali, but I prefer the sound of these).
The overall sound signature is pretty neutral, but with that dynamic driver sweetness and a very impressive treble sparkle. I am really, really impressed with the treble actually. I've heard most of the new-fangled technologies (electret, piezo, etc.) and these are up there with the best. But let's start with the bass...
Bass is impactful, very controlled, nice layering and texture and a healthy sub-bass focus rather than mid-bass. The bass reminds me a little bit of the Noble Khan, but with slightly less quantity and a little more reserved in character. Mid-bass is punchy and clean with zero bloat. It's a fast bass, impressively fast for a DD I think. Vocals sound pleasingly natural and are slightly forward with nice presentation. No complaints about the vocals. These IEMs really shine with guitar tracks and live stuff - they just sound so natural to my ears. SRV "Mary Had a Little Lamb" really makes that guitar sing, love it. Again treble sparkle is right where I like it with reassuring cymbal crashes, but no sibilance even up into the highest registers. I prefer these to any estat earphone I have heard in the treble department, but of course I have not heard the Elysium.
Comparisons...
Noble Katana: bass digs deeper on the Fusion and moves more air with the DD. The Katana has a punchier, faster mid-bass with a little more warmth, but Fusion is the sub-bass king here. I still consider the bass very fast and precise on the Fusion, but only when compared directly to the super nimble Katana does it sound a tad slower. Not a bad thing of course. Mids are a little more clear and natural on the Katana, with the Fusion having more warmth around the edges of the notes. Katana is pretty flat in its reproduction of the frequencies where Fusion is seasoned well with curves here and there
Lower treble sounds similar, but the Fusion seems to excel into the upper registers with more energy and sparkle. Neither have any sibilance and the Fusion is the more fun of the two, but I love both IEMs equally. The Fusion is, impressively, half the price and the more comfortable for my ears. TL;DR Katana is more neutral throughout the range and more natural, Fusion is a little warmer, more musical and has the better extension at the extremes.
Rhapsodio Zombie mk2: I thought this would be an interesting comparison because...I have no idea why, but why not? Zombie mk2 is a single DD with two estat tweeters and I have absolutely no idea what the crossover situation is, if there even is one, because Sammy's spec sheet is actually just a napkin with scribbles on it that he set his cup of tea on and now cannot read it. Bass on the Zombie mk2 is noticeably accentuated compared to the Fusion, going deeper, rumbling harder and slamming into the lows with powerful authority. Fusion is not bass-light, but let's just say it sits shyly in the corner of the room until the Zombie is done with its bass act. Into the mids, the Zombie is more forward, but thinner and a less natural tonality. The Fusion vocals sound better to my ears; a more "correct" sound. Zombie is quite v-shaped and sadly I think the mids are paying the tax on that tuning choice. Into the treble, Zombie is thicker and smoother, but both are highly extended and provide a lot of sparkle. Fusion sounds faster, more precise and a little more lean, but Zombie has the smoothness crown with those estats. I love both. TL;DR Zombie is a musical, fun and powerful sound that laughs at the neutrality of the Fusion, while Fusion is more natural, balanced and mayyyybe portrays a higher sense of technicality and resolution.
Again, I am really impressed with the Fusion. I think it can absolutely compete with the big dogs in many areas and at the current price it is a great deal. If you can get it on sale again, it is a no-brainer. I also want to mention that the artwork of the shells is ridiculously beautiful in this price segment. Finally, the sound is very easy to listen to and love, the comfort is off the charts and now that (hopefully) shipping and delivery issues are sorted out, I think this will absolutely be a winner of 2020.
-Collin-
These are awesome impressions, and I look forward to your full review in the future, I’m sure. 
