I own Valhalla and Siltech Gen.5. Both are great and expensive cables. It depends on your budget. There are many lower cost products out there the compete with the best, however.
Best of XLR cable?
I have just heard Kimber KS-1136 and that is my number one cabel for me so far.I never heard Nordost Valhala so Kimber is the one.I transformed my system to something I never expected to happen.My system is Meridian 808.2i,Sroll Lyric(best buy I have ever done)Tannoy Canterbury.