From what I gathered, they are great if you have the money.
I might put it differently, more like "they're (typically) quite good, but overpriced" (You say half-full, I say half-empty). If someone is interested in bang for the buck (instead of Bang for the buck), look elsewhere. And definitely don't look to Bose, either.
The BeoSound is definitely slick looking, I'll give it that. If design is worth $ to the buyer, that could change the equation. It also has a lot of features. I don't have personal experience with it but if beneteau63 doesn't need all of those features, there are definitely more cost-effective alternatives.
(For example, at the other extreme, a headphone jack to stereo-RCA adapter will cost a few bucks, if one just wants to stream from a portable player to an existing receiver).