There is one thing that I noticed that other speakers don't have is the protection features. The AV-20 has alot of features so you don't damage the speakers. Basicaly all of M-Audio monitors has these features. Even my AV-20 has them. Plus it doesn't say this but it has a fuse to protect the speakers too. You can change the fuse if it goes out. All M-Audio monitors has the fuse. You don't have to open the back cover on the higher end ones since it's external fuse. But all have the same protection features.
"RF interference, output current limiting, over temperature, turn on/off transient, subsonic filter"