You get a clean, basic look, no weird colors or overly creative "looks", but with adjustability and great highlight handling that JPEG doesn't get you.
The current builds there are quite old but we've got new ones coming.
At the moment I'm using SilkyPix for my Lumix photos and NX Studio for my Nikon photos, and then occasionally using RawTherapee and Darktable and also occasionally ART. I then sometimes attempt to use gmic on the finished JPEG or Snapseed on my Android phone for more ambience and sharpness.
I'm finding I'm spending absolutely hours on editing all the photos I take. And they don't even look that great when I finish with them, mainly through my lack of skill. I find the sharpening in silkypix to be very good.
Bump the drama and lower the white clipping point a little if you want a bit more local contrast.
I didn't know such firmware hacking was available. I'd been waiting for the GR Monochrome for years but it's a bit expensive for me.
Capture One with the same back is fine/the back went to Japan to get repaired only a few months ago and has a brand new main controller board/calibration...
Edit: oh wow, this is much older than I thought. Never mind. :)
33 megapixels is not a lot. I'd consider that fast on my 9800X3D gaming machine but moderate on my older 2700X dev machine. But of course, what you consider fast depends on your computer and your expectations.
Zooming and panning is much faster on Filmulator than most other software because it caches full-res images throughout much of the pipeline. On my gaming monitor I can rapidly zoom in and out at a buttery-smooth 240Hz refresh rate.
But actually changing settings is a bit slower.
The earliest settings are the slowest to respond since they only operate on full resolution raw data, but they're non-creative, technical decisions on highlight recovery and demosaicing and such that do not need tweaking. Additionally, you get early feedback from these in the form of early-pipeline histograms interspersed among the tools, helping you tune these settings quickly.
Noise reduction adds a lot of processing time but once you figure that out the full-res image gets cached and doesn't interfere with later steps.
It has fast (~100ms) screen-resolution response to sliders in the filmulation tools mid-pipeline but it'll take a second or two for the full resolution image to process.
Late pipeline editing (post-filmulation) is near instant even for the full resolution.
So is it fast? Yes and no. But it tries to always be responsive and provide useful information as quickly as possible.