MUSDB18 vs MUSDB18-HQ  how much is the difference?

https://github.com/deezer/spleeter says the model is "pre-trained" against MUSDB18.  I'm trying to get an idea of how much the results will differ / improve by training with the MUSDB18-HQ data.  Sometimes I hear artifacts on 2-stem at 11k or 16k on a basic track with say acoustic guitar and vocals. Looking to improve my results.  Any thoughts or feedback is greatly appreciated!