Hi there , thanks for inquiring . I feel they have stabilized as of now and if anything should improve with time . Heightened transparency/resolution over the GTX D R outlets they replaced . More truer in delivery , which in turn means more demanding of set up . I had to improve on house keeping duties , to fully harvest the bounty they bring to the table . For me , this meant DIY stents to mange micro vibs generated from play in line and power cables . Basic supports at connection points to reduce play between cable connectors at connection points to components . Over all a much more refined sound , the ease and relaxed nature now bedding in with a more holographic reach and touch stage . A Definite definite step up from the standard GTX , owners of which would do well to investigate the NCF. Many thanks to Mike L , for the heads up . Cheers !