So I imagine You (and probably many others, especially based on graph of modded) would take it in modded configuration over Oxygen, KPE, EX800ST; KXXS anytime?
Really got me interested as it is cheaper than Oxygen and about same price with KXXS. Not planning to "upgrade" till my KPE dies but will leave a mark about this.
The answer to this question is mostly yes
I sold the KPE after getting the FD02 and listening to both for a few weeks. I did like the floating mids and rolling sub bass of the KPE, but overall it was no contest.
The Oxygen - I had only a few minutes with them, so I can't fairly compare them. But in those minutes I didn't hear anything that would make me consider getting them over the cheaper FD02.
KXXS - I would be interested in hearing them. IMO, the FD02 has a faster, more textured and more even bass response than the KPE. From what I read it seems the KXXS changes the tuning of the KPE but does not change the fundamental driver and design.
EX800ST - now that's an interesting comparison.
Since I have that one, I can say more about it. It's really different, and most times I clearly prefer the FD02. It's so much more musical.
The EX800ST is designated a monitor IEM and I think that hits the nail on the head. It is accurate, revealing and spacious, it lays out the music in front of me.
The FD02 pulls me into the music. At work, I can't listen to the FD02 because if I get to a really good song I can't focus on work anymore.
Within the next weeks/months I will put the FD02 to the test against the AK T8iE MKII.
That's $300 vs $1200 MRSP. It will be very interesting how it holds up.
(Street price of FD02 in Japan is around $200, international around $270)