Brand new Nautec valve failed the go/no go thread test when being installed by my local dive shop. It’s replacement immediately malfunctioned after installation due to a badly scored seat, i.e. I would turn off the O2, purge the line via the MAV and the O2 would just climb back up to 220 bar even thought the pillar valve had been turned off. I dismantled the pillar valve and found the seat badly scored, like someone had gauges a horizontal line about 1mm deep across its face, which explained why it was unable to seal. Customer service from Nautec was mediocre when compared to Shearwater or OThree etc.