I got my V2 TWag IEM cable for balanced SR-71b amp about a week ago and put 100 of music through it, and I really do think that it's giving me better micro-detail and resolution than the stock Westone ES5 cable.
Previously I thought the stock ES5 cable was just fine with them, so I was using my older TWag V1 with my JH13Pro on the balanced SR-71b because it made them perform closer to my stock ES5, while I thought the V1 made the ES5 sound a little edgier or grainier. I think that the V2 is more musical like the stock cable, but also more resolving like the TWag V1.
I've always said that once a person has upgraded their IEM/Headphone then the next upgrades are the source and then amp - but once that's done I do think upgraded cables make a small subtle improvement for squeezing out that last bit of performance. The TWag V2 Eclipse in combination with the balanced SR-71b (and DACmini as source) might take my custom IEM as far I need them to go. I'm still thinking it would be nice to try my balanced Apogee mini-DAC fed into the SR-71b, and it will be a TWag Eclipse V2 input cable when I do that.
I haven't heard other cables vs the TWag V1 and V2, so I can't make comparisons there.