Which Nakamichi to choose?

I think, he now does only overhauls if it is the first time that he works on your deck. His 'overhaul' is not at all ES Labs overhaul who literally completely disassemble and reassemble decks and claim to make them like new or better. But they charge thousands, so I told them to go to hell. Willy does what needs to be done and tests everything in the process. I paid something like $650 the first time and about $350 second and third times. The wait time is a few months, at least it was last year.

inna

... His 'overhaul' is not at all ES Labs overhaul who literally completely disassemble and reassemble decks and claim to make them like new or better. But they charge thousands, so I told them to go to hell.

Really? You tell people to go to hell if you don't like their price? I'd say ES Labs is fortunate to not have you as a customer.

If you have many cassettes like i do some are live recordings a Nak Deck is worth the investment.
Out of the decks mentioned i would go for the DR-1 simply because it has more adjustment options.
i have owned a Nak 550 battery powered portable.
It was a great deck and ahead of its time.
i made many live recordings of my band and they always came out great.
However in my opinion The Nak ZX9 was the best deck ever made.
It was very adjustable and built like a tank.
That would be my choice.

Tandberg 3014A.

The ZX9 was Nakamichi's reference deck when it came out after the Dragon.