Dragon, RX-505 or DR-2 ?


I have the chance to get one of the 3 decks mentioned. 

The Dragon works but the NAAC is slightly out of line, it’s an early serial number which I understand can mean an expensive service. The sales price is of course the highest!
The RX-505 works as expected, just never serviced and is being offered at half the price of the Dragon. 
The DR-2 is near mint and hardly used and is priced between the Dragon and the RX-505. 

Which one one would you choose?
dmormerod
As an owner of a Dragon, I’d choose the Dragon. Regardless of which you choose, all of them will really need a complete rebuild to perform their best. Sure, they may work, but I promise you without a restoration they won’t perform to spec. 
The Dragon and RX-505 have the same transport, which was Nakamichi's best. The DR-2 was a somewhat cheaper design, although still better than most other brands of cassette decks. Sounds like the DR-2 may be priced a little high, but it would be my last choice regardless.
Congratulations! I would take nrenter’s advice and look into service. It’s worth the money.
Thanks.  Yes I've already reached out to a couple of service places, including Willy Hermann.