3 person that I know start using the Entreq ground box and Nordost as ground cable few years ago. At the beginning start with one Tellus, then Silver Tellus and 2 Silver Tellus. Using a $30US/ft silver wire as ground cable. One person think Entreq Silver grounding cable is expensive. He came up an idea, trying to use 1 strand of the Valhalla power cord as ground cable. He did a comparison with the $30US/ft silver wire, Entreq Copper and Silver, 1 strand of Valhalla. He thinks 1 strand Valhalla is the best. Other people using Tellus, single Silver Tellus and 2 Silver Tellus have do the comparison at home. And everyone prefer 1 strand Valhalla.
After 1 strand, 2 strands, 3 strands, the whole cable 7 strands, V2. Everytime has a very positive result. No one has tried the higher price Entreq ground cable, so don't know how they compare with Nordost. Someone came up an idea connecting the posts. Begin with 1 jumpers and end up with 4 jumpers on each Silver Tellus. Finally adding 4 more jumpers to connect 2 Silver Tellus together. All equipments are connected to Silver Telllus, interference should exist. But the add benefit with 12 pieces of jumpers made 3 owners very happy. Their friend in USA do the same thing, connecting 2 Silver Tellus posts together with an Atlantis Tellus.
Someone tried a ground cable from ground box to wall receptacle, the difference is very impressive. Entreq doesn't recommend connect equipments to Silver Tellus and wall receptacle together. Entreq came out the Olympus Tellus which has one post dedicate for ground receptacle. They started to discover Silver Tellus connect to wall receptacle has a negative effect if the receptacle is not a dedicate line. Even it is a dedicate line, other equipment has plugged in and share the same receptacle will have a negative effect.
At the beginning, we think connecting Silver Tellus to wall receptacle will drain away the "noise" because it works. After we know Entreq recommend plugging a Silver Minimus(nothing connect to it) to wall receptacle to clear the 'noise" in the power line. We start to think connecting to wall receptacle is not draining away the "noise" ,connecting Silver Tellus is actually cleaning the power line. The "noise" from the power line may enter back into Silver Tellus, that's why they found out it must be a dedicated line with nothing connect to the wall receptacle. One person feel that using the jumpers is not a good idea when Silver Tellus connect to equipments and wall receptacle together. He removed all 12 jumpers. Two other person still prefer with 12 jumpers.
One person try using Odin as ground cable. He was very happy with the result. He lent Odin to other people. A few person start to look for 2nd hand Odin.
All of them have upgrade to Olympus Tellus now.
People have use Nordost Valhalla, V2 or Odin power cord probably will think the background noise is very low. Also the speed is fast. This two characteristic made us think Nordost is a very good ground cable.