IMO customer service is an indication of how a company is being managed. Typically customer service goes down and so does other parts of the company.
That said, you cannot expect a company to replace/warrant a product that is used in an abusive race setting. However, the product should arrive without defect. If you receive the product defective, they should resolve the issue. Wal-Mart sometimes has horrible customer service, however, it is the person behind the counter you dislike, not Wal-Mart's policies. I have NEVER had trouble returning things to Wal-Mart that were defective (and a few things that were not =))
It bothers me to have poor customer service, however I can look passed this for a good product. I personally drive a c6BB and love it. I have always heard great things about them as well. I have never dealt with customer service. If I purchased a motor from ANY company that was defective, and that company refused to rectify the problem, I would raise hell. That would be like purchasing a racing motorcycle (no warranty) and finding out it wouldn't start because they forgot to install the piston. This however is different from a company providing some kind of warranty on the use of the product for some length of time. Under the use conditions of these motors that would not be an equitable solution for the manufacturers. Some people are going to neglect to operate properly.
Lastly, do not knock on someone for reporting bad customer service anymore than you would knock on someone for giving a good review on some product they tried. For someone to state their experiences is a benefit for us all.