I have a 100 watt/channel Sony stereo integrated amp from 1987 sitting at home. This thing is extremely heavy and build like a tank. And while it's not one of the ES-series models, it's quite a musical piece. Just wondering how long do amps last? I read about this part and that part "drying up" or deteriorate over time. I just sold my Onkyo stereo receiver and I am itching to pull the trigger for either a multi-channel receiver or one of the inexpensive SACD players.