Have had my 401A since 1959 - gift from parents for graduation from high school, Christmas, Birthday. Quite an investment then but it is my only machine and the best ever. I use is constantly from altering clothes, hemming jeans! and my straight stitching for quilting pieces. Overhauled once because needle shaft shifted (I think due to the button-hole attachment which I don't like - plastic!!).
I faithfully clean, oil and grease as directed. I am the only user of this machine.