That's really a shame that there aren't that many people that know about this. I guess the "difficulty" of coming across distancers is slightly off putting.
I should make a note that I'm using Magnum IV drivers, not the Symphones X or Magnum V drivers. From what I can tell, the V drivers have slightly less bass, and have a touch more treble. As I only have only pair of distancers, which are currently epoxied on my cups. (not coming off anytime soon), I'm leaving the V drivers as they are.
For me at least, the treble is really harsh when using the Magnum MS1000 mod, without placing some sort of foam in front of the drivers. I haven't had any bass issues ever since gluing on the distancers. While it doesn't have quite the impact and slam of orthodynamic headphones, it is very clean, tight, more than enough for my purposes.
The change I really like is the widened soundstage. It makes the headphone suitable for classical, where it does surprisingly well.
Don't expect to them to blow your head off whilst listening to dubstep, trance, or electronica. Nevertheless, it still sounds really good to my ears.