I bought the Baby Lock Crescendo in a similar experience and absolutely love it. I recently got back into sewing and due to severe arthritis, was having hip pain from the angle of stepping on the foot pedal (driving a car causes the same problem). I started using the push button and am in love. Does the symphony have the option to stop needed down pressure foot up each time? My crescendo does and it'a awesome - no need for the knee control either!
My next Baby Lock purchase is the Long Arm. I'm a customer for life!