I run dng through Resolve, so I am “stuck” with resolve super scale which is really good and fast compared to others I’ve tried, but some parts of some scenes might get extreme staircase or digital burns in for instance window frames or lamps with a shade on, so I use Boris FX or Fusion to fix it, only the really bad ones. 9/10 a normal viewer doesn’t see the aliasing or quirks like we do.
There are other way better algorithms, sorry i can not remember from the top of my head. but its 3rd party software or processes requiring transcoding back and forth. Personally I am satisfied with super scale, cause I can stay in resolve and make quick work of it.
The downside to Super Scale is that it scales the noise substantially, but you can make noise profiles in Neat Video from a base Super Scale noise sample and apply that profile to all footage and you have super clean and way more detailed image.
Super scale upscales 5d3 footage up to 2.5k with great enhancements, but upscaling to 3k, 4k or higher only intensifies all processes without gaining any more detail.
Neat Video on the other hand benefits extremely well from having the project in 4k or higher. Think of it has giving neat video 4 times more pixels per pixel to remove and replace with actual information. But 4 times more processor intensive ofc.
So i stick to 2.5k projects.