I think it’s faster than ScaleFx.
uper-XBR only does a 2x upscale in X & Y then drops down to 1x in y and 2x in x, so resolution-wise it uses a lot less memory and gpu cycles. There are also other variants in there if you want to use Super-XBR with a lighter shader, or without reflections.
Performance 4K on RTX-2060, Frames per second with ImageViewer on 224p content
POTATO 300
POTATO-SUPER-XBR 280
STD-NOREFLECT 210
STD-NOREFLECT-SUPER-XBR 190
STD__GDV 190
STD-SUPER-XBR__GDV 180
ADV__GDV 180
ADV-SUPER-XBR-GDV 165
SMOOTH-ADV__GDV 155
Test Image