I can only speak to the lenses I use and the conditions I use them in. I've avoided making blanket statements about the Fader NDs.
Anticipate having my Singh-Ray in a couple of weeks and will gladly post the results of a comparison between the two when I get the chance.
I'm eager to hear what you find. When I was researching these variable ND filters, I came across lots of conflicting info about whether the Singh-Ray and FaderND were the same product made in China or not. Some swear they are, but all I've had in hand to examine was the LCW.
This thread reminds me of the old days when audiophiles would argue incessantly about metal film resistors vs. carbon, poly caps vs. lytics, meanwhile the rest of us were listening to music and getting on with it.