Very stiff hard to turn. Low gear ratio. Hard to fine tune. Perhaps a drop or two of oil in the gearbox may help. Maby they just need to get broken in more. However the stiffness creates tuning stability. The posts don't budge, strings stay in tune even after thorough wammy bar workout! Installation was easy. With help of a straight edge they will line themselves up. Nice black finish compliments other Black EY hardware well.