FL Studio

 

It’s actually not realtime. It takes some time to process tracks first (hence maybe it’s the best out of the three).

It uses Demucs 4, but maybe not the ft model and/or with low parameters applied or/and it's their own model.

"Nothing spectacular, but not bad."

"- FL Studio bleeds beats, just like Demucs 4 FT

- FL Studio sounds worse than Demucs 4 FT

- Ripple clearly wins"