Product review (5 stars): Oh Happy Day!  It fits, and it's clean!
Oh joy!  It fits my InSinkErator Disposal; it installs easily; it's simple to get out for rinsing off.  As other reviewers have noted, it is made of lighter material and it drains less rapidly than the original.  But it's no longer necessary to clean the nasty old one.  Don't know if it will live up to its anti-microbial claims as I haven't had it long.  But I like it enough to order some more to have as back-ups.  One really horrid housewife cleaning chore is gone!