Out of all of the various plugins I've used to aid in production and mixing, SoundID Reference has been the most useful and has made a huge difference in my mixing process
Without being able to identify if my speakers or room was more at fault for the non-flat sound I was getting before using this software I can say with confidence that the correction has enabled me to mix much more confidently knowing that I'm hearing a flatter representation of my mix then before, Mix translation is now significantly less of an issue for me with mixes translating as expected to various systems as opposed to very hit and miss before I was using this correction software
My only complaint would be that the standalone software / systemwide component is quite buggy and often needs me to close and reopen the application to get my sound going through it again (after sleep or shutting down my computer, this is on Mac - Intel as well as M1), Fortunately the AU + VST versions of the software used in my DAWs is rock solid with no performance issues or bugs.