Yeah, Joe is right. The models you are looking at are decades old and time has moved forward since then when it comes to trasistors, capacitors, rectifiers, etc.
The 2505 is 30 years older than a DNA 0.5! You can't compare them whatsoever.
The MC7100 sounds great but doesn't have meters. The MC7200 (which I have) is fantastic. So is the MC2002 though it is hard to find. None of these amps have autoformers so they are the least expensive - but don't see that as a negative. The 7200 is one of the best sleeper amps so I would recommend you look for one of those. It is hugely powerful too.
Arthur
The 2505 is 30 years older than a DNA 0.5! You can't compare them whatsoever.
The MC7100 sounds great but doesn't have meters. The MC7200 (which I have) is fantastic. So is the MC2002 though it is hard to find. None of these amps have autoformers so they are the least expensive - but don't see that as a negative. The 7200 is one of the best sleeper amps so I would recommend you look for one of those. It is hugely powerful too.
Arthur