Wanted to add my input on this.
I've been using Lossless Scaling with a Dual-GPU setup for a long time now.
The last version that was launched was about a month ago (July 2025) and the quality increase is now considerable compared to the last post being made here.
I'm using it like this:
My RTX4060 as Video processor, using SVP + Optical Flow for the output at 48 FPS
My RTX 3090 Ti as Lossless Scaling GPU with 100% Flow Scale at 2X, Max Frame Latency 10 and Sync Mode Vsync, this gives the absolute best results.
Since I'm using a dual GPU setup I can also add RTX-HDR to the video output.
The image looks absolutely amazing. I won't say it's RIFE level but it's pretty close and the artifacts on the side of the screen are mostly gone, this is credit of the new update that we've received that added the "Performance Mode" for LSFG 3.1
You need to know how to mix those 2 technologies together to get amazing results.
I also think you need 2 GPUs to make it as one GPU alone for all of these processes is a little too much, unless you have an RTX 4070 Ti or better
You should try it again.