Its not a traditional keyboard diss as discussed, but I did once buy a used Korg Poly800 II from a very honest biker, a notably decent pal of a pal. He said "It works, but I don't know sh*t about it and it sounds like sh*t through my guitar amp. It also reeks of cigs and weed, so its right up your alley. $100 and its yours."
Well, it ran at 100% like a boss for about a year and then I sold it to an even newer newbie for $50, who was elated. Its the Circle of Synths.
Its also why I nearly got a Korg tattoo.