K3 pro just arrived. It actually looks better than in the pictures. Much better comfort & isolation than A4.
Though A4 is by no means bad looking but LZ buds always features weird form...
That much I can say so far, wouldn't do it justice to pass my impressions of sound this early.
Ok, after burning K3 all day, I did some comparison with A4. The short conclusion is: I will not rank K3 higher than A4, yet I don't miss A4 much when I'm listening to K3. Comparison between them would be hair-splitting, I'm obliged to say if I claim one is XX-er than the other, there should always be a "slightly" before that adjective.
Another reason it's hard to make the comparison is, A4 has so many tuning combinations, it may caters to many tastes while K3 has only 2 front nozzles. That makes A4 hard to beat. My choice of tuning combination on A4 is red back with blue front. I have them for about 2 months now, I think, and not one day goes by without listening to them. It predestines me to bias against different sound signature. That's what happened when I bought a pair of HE400I headphone after half a year of psychological burning-in with er4s, HE400i sound unbearably distorted and I just wanna throw them away if not for the money I paid...
I don't feel that with K3. Actually before I A/B it with A4, I hardly notice any difference. While A/Bing, A4 sound to me has a larger soundstage, but K3 is no slouch and more 3 dimensional (slightly, there always is a slightly), instrument separation is better with K3. Treble extension I have to give to A4, piano playing is more realistic. Mid-range is clearer on A4 too. Bass goes deeper with A4 but more controlled with K3.
When I was watching a TV show with A4, there is this scene that the clock-ticking is annoyingly present in the background, and I switch to K3, the ticking is present but no longer annoying. I believe that bespeaks the detailing level between the 2.
At this stage, A4 is still technically better, but K3 is more than able to enjoy music with.
Beside sound, they are both very well made, I have no complaint with either. Comfort and isolation as I said before goes to K3.
There goes my subjective comparison. (A4 2 months old, K3 1 day.)