They suck big time. Had them and hated them.
I've used Duelund 2.0 V2 silver for internal speaker wire but not for interconnects. This wire initially sounded rolled-off, but after long break-in and further improvements to other components, the correct frequency balance has been restored and everything sounds great with a more natural rendering of HF and calmer background suggestive of reduced noise floor. Piece parts with low resonance properties may lead one to reevaluate how much of what typically passes for HF extension is a artificial resonance product. YMMV until the system has been sorted from end to end.
That said, the spiralling costs of precious metals leads the brain toward copper.