These things are one of those rare exceptions to the rule consumer electronics are cheap disposable crap. With above average power and sound these stand out. Altec is a "real" speaker company and the only one in my mind that made a serious effort when designing computer speakers. They're engineered like no other computer speaker and are the kind of thing you'd expect Mercedes Benz to make if they made computer speakers.
I bought my first set around 2004 or 2005 and really haven't found anygting else that gives as good sound. The V4121 is relatively common and more than adequate for most use, the four channel systems are more interesting as they seem to decode modern multi channel recordings just fine, by I assume, wizardry.