Thanks for the advice. I'm going to post a new thread to see if I can get some additional advice on some newer amps.
Although I have never owned one because of their cost, Aragon amps have always been noted as one of those in the audiophile/high end category, hence. assuming it is in good working order, in good shape and the price is right, I don't believe you could go wrong there. In addition to sound quality, well built amps are usually very quiet and the 10 year old Aragon should compare favorably to anything built today, regardless of cost. Frankly, I was not aware that Nakamichi ever built power amps so I am totally unfamiliar with the model you described.
Power amps should last a long time, 20 years, at least, not being unusual.