Most common problems with this unit are drain pump, lid lock, and accuator (changes transmission from wash to spin). Originally they had issues with the pulley coming loose, although most of those were fixed under warranty. On some of the oldest of these models, I am starting to see broken wiring issues. You are correct, that they do only a par job with really dirty clothes.
Cash donations always accepted.
Bearcat
P O Box 8
Hiwasse, AR 72739