Mine was the opposite experience. It wasn't really the same situation as yours, so maybe this is totally irrelevant. But here's my story, just incase.
My health insurance denied my coverage for a Dr's appointment ("pre existing condition") a month or two after the appointment. I had moved by then, and apparently the mail didn't get forwarded or something. The dr's eventually turned me over to some California collection agency who then wrote letters to the same address, with the same result. They did leave an incoherent, mumbling voicemail once, which sounded like a telemarketer (hence I ignored it).
To my eternal horror, my credit score dropped from 762 to 630 in June. Over 130 points, over an $80 bill. This means I went from "higher score than 86% of Americans" to "higher than 24%".
It has utterly destroyed me. I have no credit anymore. I've been too scared to even apply for another credit card (I only have one), even though "you're supposed to every N years", for fear it would drop my score even further. I have a wife, and our credit prospects went from "could not be better" to "completely, utterly screwed. Good luck if your car dies. Also, good luck getting any kind of AT&T service, Internet service, etc etc when you move again."
They showed no remorse at my situation. The lady assigned to my case even directly hung up on me when I expressed annoyance about her not attempting to contact me more... Thoroughly... Before she decided to ruin my family's financial life. I immediately called back, which rang and rang until reaching her voicemail. I contacted her manager, who said that the lady assigned to me was the final authority on my case, and had not acted inappropriately by hanging up. Nor did they care that the mail hadn't reached me. The worst part was, I had the money the whole time. I would have paid.
Don't take bill collectors lightly. They'll break your family's financial knees over $80, as they did mine. (Edit, clarification: they will report your bill as "seriously past due 90 days / account in bad standing" or some such, which will destroy your score at all 3 of the credit bureaus; hence, the whole system will break your family's financial legs.)