The 1-Ohm mod works really well with the LCD-2 and no doubt with some other headphones, but the default 10-Ohm output impedance is surely the better way to go with still other headphones.
I suspect that CEntrance decided to make the 10-Ohm impedance the default because they believe it would sound best with more headphones than would the 1-Ohm impedance. So, even though 1-Ohm sounds GREAT with the LCD-2, in my opinion, it can't be great with every headphone and every person's taste.
In my case, I've never heard a DACmini CX with the 10-Ohm output impedance, but decided to order the 1-Ohm mod because I read that several LCD-2 owners prefer it -AND- CEntrance describes the 1-Ohm mod as being more neutral sounding - which is a trait I personally prefer. Lastly, bluemonkeyflyer writes that the 1-Ohm mod sounds brighter than the 10-Ohm mod - again, a trait I prefer - I don't like "dark" chains.
I've tried my DACmini CX with 1-Ohm mod using the Shure SE530, this evening, and I don't hear any hiss, by the way.
I hope that helps,
Edited by zilch0md - 9/20/12 at 12:59pm