I've been wondering if it's better to leave the pop-out castor wheels IN on a gig or take them off? The guys in the band like to feel the stage floor so they like them out. Sometimes on a typical wooden stage..(hollow) I think it's better to leave them on...to de-couple them from the floor maybe? Then I started wandering what would be the best thing to do on a concrete floor? The reason I even started to think about this was after seeing those isolation stands for studio monitors in a catalog. I know I've read some things about this subject while cruising online, but I really can't remember the definitive solution. Any acoustical engineers out there? What do you think?