Hi my friend,
are you talking about my 2 apps?
QualityScaler has 3 heavy, high quality models, while RealScaler has 2 models:
- RealESRGAN_plus_x4, that is heavy, high quality model
- RealESR_generalv3_x4, small and fast model, but with reduced quality
so, if you are interested in quality you should choose QualityScaler, while if you want speed you should choose RealScaler with RealESR_generalv3_x4
:)