There are few things so valuable as a good user who is willing to work with you. Many years ago I worked at a company that was going to shutdown a very buggy product. There was one user who relied on it heavily and convinced the CEO to make one more release, and I was tasked with working with that customer to make it happen. Over the next month, we fixed the bugs (I coded, he tested). We wound up making a stable and more user-friendly product. It was a real pleasure to work with that guy. The company still mothballs the thing, but I know we had at least one happy customer in the end.