Sold a V-synth once..
Kep missing it, and bought a v-synth GT
Which i traded for a V-synth XT and a Yamaha ex5 rack
Both got stolen, with the rest of my modules colection..

Still miss the V-synth however, which was probably my favorite synth ever.

Also replaced my Roland G70 for an audya 4, which was broken and never really got it to work.. i think i kept missing the G70 mostly because of the audya 4 not functioning..
Many years later i got to own another g70, but it definately could not keep up with the T5, almost never used it, after i sold the T5, i traded that old G70 in my deal for a pa4x.. best deal ever

And then there is the Kronos, i sold it after owning one for a few months, back then it was to advanced for me, now i own 2 kronosses.. the 2nd was such a great buy, i could not withstand it.. i love love love the kronos. But i guess i will sell the 2nd one soon after having serviced he keybed and make a good profit on it.