I am the band director at a small Catholic High School in Toledo, OH. I have purchased (2) 24" iMacs (25lbs) for my practice rooms as we are installing SmartMusic so the students can get more out of their practice. I would like to mount the imacs to the wall both for aesthetic purposes and the fact the rooms are a little small and I do not want to give up the floor space to a desk. I am looking for something small but strong. The walls are cinder block, I don't know that that matters from mount to mount but I want to be thorough. I do need it to tilt. I do not want an arm because I am concerned with it coming in contact with the door. What have you guys used? What would you suggest I stay away from?