I just recently started to use MB, after what seems a lifetime in the iTunes world (the whole family has been iPhone users). But I can clearly see now that a better solution was out there.
I am currently at 25425 tracks, on 2067 albums, with 768 album artists. Disk space is just under 583GB. Most ripped from my CD library in ALAC (again, needed due to iOS influence), with some lingering mp3's from more than a decade ago.
The bigger challenge has been converting my vinyl collection to digital. So far I am at 167 albums. The transfers are in real time, plus the work to separate the tracks and clean them up before tagging. On a good weekend I can get through 5 or 6 albums. For now I am using 24bit/96kHz sample depth and rates for these, since disk space isn't as much a concern as it was back in the early days!