I am so sorry to hear about the problems some of you are having with the walking foot! And, the walking foot fell apart? That I am not sure of why. Maybe the new ones are not made very well.
I purchased 1 a few years ago from Hancock Fabrics with a 50% off coupon. I love it!!!! The worst part is remembering to put the funny looking slingshot finger onto/over the screw that holds the sewing machine needle on, BEFORE I attach the screw to hold the walking foot on to the foot pin. Once you master installing it - you will love it!!! And don't try to be a speed demon! LOL