I've heard the SM350, but not the Classic 3. I did a/b the 350 with a Klipsch RB51. Despite the RB51 having a horn loaded tweeter I found the 350 to be much more harsh to the point of being unlistenable at loud levels. I also found the supposed 26Hz extension of the 350 to be rubbish. The RB51 had bass that was deeper and tighter. In case you can't tell I was unimpressed with the 350.