If you have a use for a speaker that plays best LOUD, Then you might want the Mach Ones. I bought a new pair in 1977. Sounded great with "Aerosmith" and "Rush" played at party levels, But for more laid back music you listen to at reasonable levels, I think your Missions are in a whole different league. Much more balanced.
I have always been a fan of Realistic equipment and wouldn't hesitate to buy one of their products if I wanted it. I'm glad many folks won't, Keeps these hidden gems price reasonable. I found them to be an outstanding value overall. Although their Mach ones are one of their most recognisable speakers, I think their Nova series speakers and T series towers are a far better choice. Much like the Missions, a smooth and well balanced sound at any volume,