Re: Is the 59/custom hybrid brighter or darker than the regular SH-1 59?
If you're looking for something heavy and tight, stepping up to the Custom 5 might be what you're wanting to hear, but the C/59 does have a nice output, texture, and growl that makes it a very good pickup in the Duncan lineup.
One thing I always liked about the 59 is it's sustain and ability to sound beautiful with cleans, mid gain, and high gain. But it does have that 'almost there' type of output.
I kind of think of the C/59 as Van Halen, and the Custom 5 as Alex Lifeson, as a sort of tonal reference.