Most of the high-end manufacturers I've dealt with have been excellent. These include CAL, Krell and McCormack. But, by far, the one that stands out is VPI. These folks really care about their products and, perhaps, even more so, their customers. They will bend over backwards to accommodate you and make certain you are getting the most from their wonderful products. If you are analog-inclined you cannot do better for yourself than VPI. Creek and Celestion have never answered my emails. I figure they're still peeved at us Yanks for that 1776 thing. Sony shouldn't even be mentioned in this forum! They are a mass producer - perhaps the massest - that only cares about moving product. Their customer service, such as it is, is hideous. Some years ago I swore never to buy another Sony product of any kind and have stuck to it. In the product categories you might found yourself shopping Sony do yourself a favor and go with Panasonic, among others. They are not going to give you "high-end" service but they will help, which is more than Sony is likely to do.
Best and Worst customer service?
My vote goes for Sonic Frontiers, as Best! I was contacted within an hours, after e-mailing a question. Wery friendly and helpfull!(they can count me-in on the next purchase) Thw Worst? Linn audio! It's been over a month since i submited a Q! I am stll e-mailing the question...i am sort of amused by now!