I use Gen 6 Ultra. They get better with the cost. My choice was based on my components / budget. If it starts to be a major percentage of the cost of your component... then upgrading the component becomes attractive.... and of course with a much better component then it will be more sensitive to improvements in cabling. My average component cost is around $20K, so Ultra made sense. Generation 6 was a big improvement over Gen 5 and earlier by the way. The performance bump made the lower level Gen 6 outperform one tier up Gen 5... at least in some of the tiers.