Received my V6S's a couple of days ago, and as I am typing this post I am still letting the fact of how good it is sink in (I didn't expect it to be that good; I already thought my ASG-2.5's were really good). I have to say it pairs really well with the DX90.
Bass quality and quantity is superb - it's tight, full of impact and they never interfere with the mids.
The mids are just mind blowing! I can easily hear tons of details in vocals that I had to focus really hard using my ASG-2.5 to pick out, and the mids are simply alluring.
The highs, although I wish there could be a bit more, are well controlled, and almost never exhibit sibilance IMO.
Soundstaging is really impressive. Although the soundstage is not massive by any means, depth reproduction, width and imaging are superb.
They are only a 100SGD more expensive than the ASG-2.5's but IMO they're clearly a level up.