Moon, issue here is not about your Utopias. So don't even bother focal people more with that. They must be fine. The fact of the matter is that people here think that you have been commercially selling. So yes you've rightly said, posting the Sr. Numbers of PS165 that were sold to different people would suffice.
Rest i strongly suggest that you should not comment on his professional career, being a Dr is a noble job. I have seen him do 18-20 hours shifts staying 100% alert. Lets not go there.
And the part of chat that was posted by Dr, in that you didn't use gentle words to suggest enquiry regarding the item being bought. It wasn't nice, any humble person, finding out that he's being called a cheat would mind that. Since this is an open forum, if you could share the evidence of that amp being bad, we would surely hold Dr accountable for that. However, if you or a friend of yours bought an amplifier and it didn't turn out fine, but i think you should've contacted the seller right there right than, rather than say this behind his back. Otherwise it makes the buyer guilty. You can't go to a shopkeeper or a user after quite an interval and tell him he sold you broken thing.. consequences may be something the buyer may not like..
Now the third side of the picture, maybe it was the installation guy who wrecked the amplifier. Maybe it wasn't even a fault to begin with. Now that matter cannot be closed with sufficient evidence, since its long gone now.
For the sake of everyone's respect here, i suggest that we should not get personal. This is a public forum, if items bought / sold have trouble, matters are to be discussed openly. Focal is a very good brand nothing wrong with it. Lets not confuse the upcoming buyers.
Moon, i'd suggest that you drop the matter of the old amplifier and share the details of PS165 sold. And from there onwards, this matter shall be deemed resolved. No accusations / bitchin by any party regarding anyone. We're civilized educated gentlemen here, lets behave that way.
I request other members not to call anyone names either.