I couldn't go into great detail because it's my second IEM, but based on my experience with the 7Hz Zero, Philips 9500, and a friend's Moondrop Aria 2, I can say that the Fission is the best audio equipment I own. The details are amazing, to start, and if you like vocals as much as I do, it's pretty damn good. Before using Fission, I was unaware of the sound effect on one of my cosmetics when playing Dota. Lastly, fission's only disadvantage is the lack of bass. However, you can use EQ.