I love my knee lift! I learned to use my left foot to use the foot pedal and my right knee to lift the presser foot. Using different legs for the different functions helps avoid confusion.
On my Bernina I have the knee lift for the presser foot and then if you tap the foot pedal with your heel it lifts the needle so that your hands never have to leave the fabric it is awesome. I love it. It helps piecing, especially chain piecing go so much faster.