Which Nakamichi to choose?

@jond , I agree with you; I tried it and decided against using it. I think everybody back in the day tried it and came to the same conclusion.
  I still have tapes that I recorded with "Dolby On."

It's true that the many cassette decks suffered high frequency loss using Dolby Noise Reduction, however this was not an issue with the better Naks. I have owned a Dragon, CR-7a, 670ZX with NR-200 Dolby unit, RX-303, 581Z, and still have my original 582. None had a high frequency loss using Dolby.

@terry9 , the CR-7a must be like "studio quality," (I realise we're talking cassettes).

Would Dolby B on a stock CR-7 effectively reduce noise w/o limiting sonics?

Thanks for that info, @tls49 . I still love analogue tape and have considered a used Nak to archive vinyl.

Was Dolby C of any use on the Naks?

mickeyblu79,

DR 2 is as good as you will ever want it to be. I have no experience with DR 1, though.

Practical difference between cast and stamped metal has probably evened out over the last 25 years. If they have survived, they have proven reliable enough, I would say.

If you are really a cassette novice, you should know that the medium is very inconvenient and novelty may wear off relatively soon. Otherwise, it does posses some magic. If you still have your own tapes from when you were what you are not anymore. It does bring a madeleine moment every time and many of us love it for that. Some admit, some do not. I have to admit that recording new tapes is not as exciting as it used to be, but playing old ones is unbeatable. It beats playing records.

There are tapes to be found, but you will have to learn which ones you really want. TDK SA from 1980-1988 seems to be indestructible. SA-X comes close. However, it will be a real luck to find them for 25 cents a piece. Same tape names from the 1990s, at least on my machines, have had different (less tight in some imaginary way) sound and were far from reliable.

Good luck.