Okay, so now that I've had them for 12 days, I'm ready to give my impressions of the kegs.
Out of the box : The treble was extremely sharp. I instantly switched to foam tips to see if they helped, but I had to them down after 2 songs... It made my ears pain and I regretted my purchase decision.
Decided to burn them in and see if it changed anything. Paired them up with my retired HTC One (M7) and run them at about 80% volume for 4 days straight.
Now I know that the whole burn-in theory has been discredited a billion times, but the sound was instantly, very noticeably different. It no longer hurt my ears and the soundstage is glorious!! The treble is still sparkly but it's very enjoyable and no longer painful. The sound is pretty flat otherwise, with a minor recession in lower-mids. This was easily fixed by a small EQ adjustment.
It's hard to drive on my current phone (Xiaomi Mi5), but works flawlessly on my old HTC One, Desktop's on-board sound (MSI Z97 using ALC1150) and through E10K on my laptop.
I think that the "bass-heavy" or "V-shaped" impression that people have mentioned is in-fact due to the midly recessed mids in an otherwise balanced set of earphones. With my mild EQ-ing, the sound is perfect and flat. Tight bass, sparkly (but not overimposing) treble and no-compromise mids. However, the biggest highlight to me is the sound-stage which sounds absolutely mega, coming from a Vsonic GR07. Day and night difference.
Comfort-wise, the foamies I got from the-one-who-must-not-be-named are kind of meh, I don't get a perfect seal either (keeps trying to slip out)... I intend to buy some comply foam tips and then these earphones would be nearly perfect.
Editing to add an afterthought : As someone who heavily relies on numbers, stats and science, I find it hard to believe that the sound could change so drastically after burn-in. Is it possible I managed to damage one of the BAs, which were handling the ultra-highs, resulting into me getting rid of the painful treble?