Opinion on Nakamichi azimuth tape decks please


I am thinking of buying a Nakamichi tape deck with the azimuth head adjustment. It will be used mostly for playing of old tapes (that's why I need azimuth). Nak made few of those: 670ZX, 680, 680ZX, 681ZX, 682ZX, Cassette Deck 1, CR-7A, DR-1, ZX-7, ZX-9 and the Dragon. I would not like to spend a lot of money so the Dragon, CR-7A, and ZX-7/9 are excluded. Any opinion on the others? I assume all of them have excellent sound quality; is it true?

I have read that the 680 models have very reliable transport mechanism and other components, but they were made almost 30 years ago. Anyone have recent experience with them? The Cassette Deck 1 was made in 1990-92 (don’t know about DR-1); how reliable are they? Do all of the old Naks require frequent calibration and servicing, and how expensive is it?

Any opinions will be greatly appreciated.
prophos
I don't believe that any deck other then the Dragon had auto azimuth adjustment. Could I be wrong?
Manual azimuth is not that hard to use but I do think that the Dragon is the only Nak with auto, not sure of any others.
The Dragon, and I think the 1000zxl or xzl or whatever it was called also had the auto azimuth adjustment for playback. I use a dragon myself for cassette transfers, but on occasion I've come across a tape that will have not enough in the treble range to allow the dragon to lock down the azimuth, so I keep a Cassette Deck One with manual adjustment for those rare occasions.
I have a 670ZX and it has Auto Azimuth Alignment, it says so right on the front. It's a very nice deck and unless you're a perfectionist it should do the job.

There are still a lot of old Naks around so you should be able to pick up a nice one pretty cheap. Shop around and get one that's in excellent operating and cosmetic condition.