One big expensive mistake I made was trading in a Logic DM101 with an FR arm for a Linn LP12,Ittok,Asak. Sold the Linn and replaced it with a Townsend Rock Ref which was far more accurate to my ears. I've never regretted selling anything in HiFi I have to say. I have paid good money for gear I've not got on with in the long run. Shahinian Compass speakers come to mind and AE 2's with their foam surrounds that rot in no time are others. Amps I have owned but not enjoyed include Nytech 252 Receiver and Linn Clout power amp.