I'm seeing lots of good reasons for keeping a full QA team around, want to add one more: They're basically the only people that know everything about the produc

I'm seeing lots of good reasons for keeping a full QA team around, want to add one more: They're basically the only people that know everything about the product. More than product managers who generally specialize in the Foo feature, more than the engineers, certainly more than sales. When a seriously complex support issue comes in, they are always the most valuable people to take a look. To me, the value of QA is more about product knowledge and expertise than just "testing things".