I'm a happy owner of a 4B ST since the late 90's. Only serviced the amp once when the speaker terminals had loosened. Communication with Vermont service was exemplary. Real people who respond promptly. Had the amp back in about ten days. They also cleaned up the amp and sent it back in a new box. You can't beat their 20-year warranty. Since then, trouble-free. The sound is very clean, neutral, non-fatiguing, and transparent. It will reveal the best (or worst) of your other electronics.
A shout out too to PS Audio, another company with great customer service. My PCA-2 Pre-amp has been trouble free for 13 years of ownership. Recently the remote went loopy. Been working with their service department on solving this. Haven't solved the problem yet but they've been extremely responsive and attentive, and we're continuing to troubleshoot; been even sending me replacement remotes free of charge.
A shout out too to PS Audio, another company with great customer service. My PCA-2 Pre-amp has been trouble free for 13 years of ownership. Recently the remote went loopy. Been working with their service department on solving this. Haven't solved the problem yet but they've been extremely responsive and attentive, and we're continuing to troubleshoot; been even sending me replacement remotes free of charge.