The old 3150s (integrated amp) and 2150s (power amp) were terrific amps, especially when bridged. I had a 3150 and a 2150 in briodged mode and those amps kicked serious ass...
I have owned a few NAD power amps and never liked them.The Power Envelope ones like the 2200 sound especially poor-good bass amps but very 2D sounding.A shame because the preamps are excellent.The 1155 that was sold with the 2200 power amp was superb and came with a killer phono stage.
It would take an exceptional amp regardless of age to sound better than an Accuphase P300.[I own one and have had all sorts of modern SS amps that do not come close]
Only modern tube amps will do that.
For not much money you can buy a Ming Da EL 34 A/B tube amp which is a brilliant allround amplifier.
I think that you do get a good bang for your buck from NAD and Rotel.
I have used both of these with better pre-amps and they are worth the money used. Look at a used NAD C-270. Great bang for your buck. I agree that the Accuphase will be better.......cleaner and more musical.
I do have sales feedback on this site. I have experimented
with a few.
Make sure you have a good source!
I took a 2200PE and remove the horrible hard wired stock power cord and connected a good power cable to the transformer primary. I plugged it into and used the Monster Powers switched outlet as the on/off switch. That really improved things.
Still its just a "decent" amp and a good value. Nothing to write home about.
I bought new in 86-7 a 2200 and the 1155 preamp.All I drove were Bose 901's for a couple years.Then I brought home a few different speakers like these big ADS and some Yamaha NS10M and something else.One day I brought home a Nakamichi CA5 preamp and it was like a blanket was lifted off the speakers.Then I went to Threshold,Levinson,Bryston etc.I would not go far to get these particular models.Everyone here has their own story,so good luck and MC,Bob