If you're looking for an immersive IEM with holographic soundstage, deep powerful bass with excellent punch and control, a forward and articulate yet velvety midrange with rich textures and last but not least engaging treble with excellent extension then look no further, Zen will offer countless hours of musical bliss!
If you're looking for a highly engaging comfortable IEM with excellent craftsmanship, with punchy, quick and dense bass for a superb sense of rhytm, full bodied mids with bite and emotional vocals as well as energetic and well extended treble then at this price point the Insects Awaken is a no brainer in my opinion!
If you're looking for a solid technical performer with a reference tuning at a reasonable price, boasting strong bass foundations, articulate and clear mids as well as energetic and well extended treble that provide both excellent resolution and imaging then the Spring 2 is a strong option in the lower price tier!
If you're looking for a full fledged flagship cable that brings the intensity up a notch on all your IEMs with snappier and punchier bass, fuller bodied mids with superb bite and separation and energetic yet smooth treble with superb transients without breaking the bank then look no further!
If you're looking for an IEM that boasts one of the best soundstage at any price, features powerful, clean and quick bass with excellent control as well as a clear, open an articulate midrange and a well extended and engaging natural sounding treble then the FD5 is a no brainer! If you own a good copper cable I strongly suggest you plug it to the FD5 as it will be a more relaxed yet engaging listen and if you don't it's worth spending the extra money unless you enjoy a more energetic and brighter midrange. I would stick to the larger nozzle as the narrower brings most of the benefits a copper cable brings with the downside of making the soundstage smaller and penalizing the upper treble presence and the engaging lower treble.