I've had these for a several months now, I was amazed when I bought them and they continue to amaze me.

I've had my share of Etymotics, Westones and Shures, over the years (and with flights and funds increasing) upgrading through their ranges. I've also been upgrading the sources; having rediscovered mobile music (from Walkman days) with an iPad mini, then various Nanos, then phones.

I bought these last year and they made a massive step-change in what I thought was possible in every sonic aspect vs the previous portable gear I'd owned or heard. They even challenged my main stereo in terms of resolution; both disturbing and impressive at once.

Being so capable, they sent me down the source upgrade route - I velcro'd a Vorzugge Pure amp to my FLAC playing iPhone. Then bought an AK100, and strapped that to the 'Pure - and now I have an AK120.

I can bore you with my impression of the sonics etc; but my point with this story is that these earphones produce better results with every improvement in what I feed them. I'm hearing whole things, not details, in music I've had and loved for decades. Yep, they're bloody expensive for earphones, but I believe they are pretty much future proof; sources will get better faster than these will date - and when they're finally overtaken, it'll be a minor miracle - and probably worth the upgrade price!

I've mentioned elsewhere on here how I preferred these as I felt they were more balanced and neutral (I love big extended bass, but not at the expense of overall balance) than another top end unit I tried, but whatever your preference, I can highly recommend splashing a good proportion of your HiFi budget on really good IEMs. These FitEars get a huge endorsement from me of course - but never mind that, go and spend a mildly embarrassing amount of money on the best earphones you can afford - you'll get over the buyer's remorse after a few tracks!

Cheers
Andy

The first bars of the 24bit version of Massive Attack's Unfinished Sympathy - I got my wallet out.  More detail, soundstage, bass, more finesse, more power and dynamics (I listen to the AK100 in isolation at around 47-50, currently listening to the AK120 at 39 - whether it's exactly the same scale, I don't know of course)  However, I don't need to strap it to the Vorzugge Pure to get the extra punch that combination offers.  The software has a grid interface which feels like progress, and it seems to be more responsive in use.  Retina doesn't apply though.
 
So, I'm delighted - again.  
 
Is it perfect?  No; the volume knob feels much more sturdy and has some protective ramps either side - but it still seems a little unnecessary and is still too tall.  I am currently having a bit of a problem with the SD cards, it's forgotten them twice now, alternatively.  I see the firmware version is 1.0.  I'm not sure if it's the same as the AK100 (currently at v1.33) the interface would suggest not? Anyway, I'll try to update it and see if that fixes the card issue. Registering tracks seems to take a long time too, but no change from the AK100 there.
 
Overall, it has to get a 5 star review as it simply sounds superb - Skrillex has just made my brain resonate in the middle of a huge soundscape.  Now that's worth the considerable amount of dosh it's cost me - anyone want to buy a barely used AK100/Vorzugge Pure rig?
 
Hmmm, I'm just wondering when the AK130 will hit the shops...