interconnect XLR cables Valhalla Nordost or Reference XL Transparent?

What kind cables is better?
Your question as a general OP is an impossibility to answer:

(1) Commenting on performance for a set of any XLR cables in isolation is no measure of meaningful success or failure, nor any meaningful suggestion towards "better" or "worse"..

(2) the performance of any cable is entirely dependent on the strengths AND warts provided by both of:

a) the synergy (or lack of it.... ) with the rest of your system; ( that's the alchemy produced by that mix of ALL of: your source, your electronics, your speakers, your speaker cables and your power cables); that is further influences by (b) as follows.

b) the unique impact provided by (and thus impossible for others to comment on..,) the nuances, challenges and other similar bespoke audio performance effects  (+ or -) invoked by your particular listening environment .

Simply put,  there is no absolute or prevailing general "best" option, and one size does not fit all.

 There is negligible to nil differentiation at the cheap/ budget cable price strata. However, at the lofty IC price point you have pegged, its only your personal audition (with reference to the points above) , that can diffentiate a contender from the pretenders.