Setup: Foobar - Flac 44.1/16bit or higher. Headphone out directly from XDA-2 which I find superior to most portable amped sources for IEMs.
My history: An older brother taught me critical listening at an early age. The unfortunate result being that my 20s and 30's were mostly completely music free since I could not stomach the regular fare without the capital for investment into my own equipment. Headphone technology has drawn me back in on the cheap. To say I can be harsh or critical of equipment regardless of cost is sometimes an understatement.
On with the rambling ...
My impression:
Honestly, to say that the W30's are superior to the higher numbers in the product line I think is a large leap. The W40's are superior in complex passages and leave the W30's in the dust.
For instance, Dead Can Dance / Anastasis / Return of the She-King peaks about 5 minutes in and starts to get quite complex across the spectrum. With a bass drum, male and female vocals, snares, horns, violins etc all set to a huge reverb of this just massive space is normally quite compelling. With the W30s Lisa Gerrard's voice becomes flat an nasal. The whole cohesion falls apart and the space is lost into a flat wall of noise. There's simply just too much information and all the spacial cues fail.
I agree they are a 'fun' and edgy, and the W40's might seem a bit dark by comparison. But on careful listen and contrast the W40's while smoother still carry more detail and don't suffer from an etched sound in the upper midrange like the 30s. They can also hold, separate and call out instruments in complex passages. The 30s simply didn't pull this off for me. The 40s while missing that top tier sparkle, they do have enough to say that you can forget about it. The 30s have this in spades, but it can also be distracting. I'll go further that the 30s don't really anything glaringly wrong at any individual frequency. The issue with them seems to arise when things get complicated.
Musicality:
On the Alum "Mickey Mouse Operation" by Little People the track 'Idiom' quite frequently in the right mood and equipment will give me gooseflesh on the arms. I wasn't finding that with the W30s. The W40s will often get me there. That's why were here right? No matter how good of a technical performance you might get out of your equipment, if your music doesn't get you off - your doing it wrong!
The W40s pull me in. Stop me in my tracks, stop me from typing on head-phi.... I'm not getting any of that in the W30s. They don't relax me and allow me to let go.
Conclusion:
The W30s are full of grit and detail, but organic? No. Maybe a hair dry I might say, but that would be splitting hairs. They aren't terrible and for certain they out perform my Shure SE530's which I find don't even hold a candle to the W40s. I did audition the W50's but I didn't think the jump in price had merit. The 60's were not yet available at that time and I have yet to take out the time to find a pair to try. My wallet says I shouldn't. Someone previously called them out as 'only a bit more holophinic'. Well, I don't know about you, but I like solid spacial representations of layered dynamics and textures. Sigh. What?
Do the W30s perform well? Yes. As a mental exercise however, I would drop them into the $200 IEM category. Comparably, I personally also see the W40s as a $300-400 IEM. I know the market doesn't agree with me with its rapidly inflating prices, but there you go. Maybe I'm living the past.
In simple music without complex passages (EDM/Calssical /Strings) the W30s do really shine. However, fact is that if you have a varied taste in music and you are currently busy climbing the head-fi ladder then I would possibly suggest you pass. Then again, if you have some disposable cash, give 'em a roll. They are fun!