Need ST/AT&T cable for metronome set

Hello all,

I'm looking for nice ST(AT&T) fiber glass cable for between
metronome C1A DAC
Trans T1A

The budget low, about 100-150 $ Don't mind for used ones .
I see lot of brand on ebay but not sure what is ok.
(there's too many sizes ...)

heard that ST work's better than any other cable type .Is it true?
can some1 explain why ST is better the tonsil if both connection are fiber optic and data transfer is digital?

Thanks