I've only used their customer service once when I was having a problem with my Kindle 3G. I was completely and utterly shocked when I received a phone call from them in under 5 minutes from when I submitted my form.
When I saw that I could expect a quick turnaround, I scoffed because I'm in Australia and I thought there was no way they would give that prompt service to Aussies (cynical guy that I am). Suddenly I have a phone call and I was gobsmacked.
As for the service in the call itself, I don't think the response was brilliant in the end and there could be been better ways to go. It did actually solve my issue but it was more a brute force approach (factory reset) to what was most likely the classic indexing problem. At least he got me to back up the contents of my Kindle before he had me wipe everything - so could have been worse.
