I used to use Media Monkey and I liked it, but I removed it for reasons that I can't remember now. Perhaps a susceptibility to a virus? I remember that I lost all the tracks.
What I liked most about it was what Bill D said, when playing back on the computer, you can/could set the volume level so that all tracks played at a compatible level.
I never found a way to rip a track at a set level into the library, or to export it at a set level, it just noted that the track was to be played '+3' or '-2' or whatever within its own system.

This was a couple of years ago.