...
No just no. I already tried with Sundara (2020) & Edition XS (Balanced Out with both). It can get enough volume out of them but overall it cannot drive them to their full potential. The overall sound while loud enough is Bass anemic, thin and bright. Even the RU6 does not drive them well.
What
@scracy said. Although with the BTR7, I noticed that the difference between Balanced and Single-Ended while present, isn't that big as long as you are trying to drive IEMs that don't benefit from the extra power. Some of my previous gear with Balanced circuitry like Sparrow, Gryphon, BTR5... where much more softer and intimate from their Single-Ended Output compared to Balanced Output which had wider soundstage, better Imaging and clarity...
Try XINHS Cables, they are good value for money. I recently got one 8 core cable (If I remember correctly, attached Pic) from them and it has good build quality, better than other alternatives like KBear, Tripowin... and feels good in hand too. A bit heavy though so maybe look for less core count cables from them of that's an issue for you.