I never gave up my Sony TC-K808 ES. It's a machine with all the bells and whistles, from dual capstan and quartz control, to three heads and manual calibration. True, it hasn't seen all that much work lately, but I just don't see myself without it.
The two problems associated with cassette and open reel format were wow and flutter and head azimuth. If the tape you are listening to has been made on a poor machine, it makes no difference if your deck has very little wow and flutter because it was also recorded on the tape.
Azimuth was also a problem. Obviously, different machines were adjusted with different deviations from ideal. If you are unlucky, and your deck is at the plus deviation extreme and the one the tape was made on was at the minus extreme, you would end up with a mushy sound, little or no highs, etc.
Therefore, if you own one, or are thinking about buying one, make sure you have somebody reliable with associated gear (test tapes and an oscilloscope) who can really adjust it well. Do that and you will like what you hear.
While Nakamichi was considered king of the road with their Dragon model, there were other products out there which could stand up to perhaps not the Dragon, but other Nakamichi decks. To name but a few, there were ReVox/Studer, Sony, Tascam, Pioneer and some Denon decks (probably others as well). If you are scouting for a decent buy, make sure it has three heads at least, and try buying a demagnetizing tape, TDK used to have a good model. You will need it.
Also, try finding a deck with a manual calibration rather than automatic. Autos were quirky, they could play weird tricks - never liked them.
Of course, I also still keep my open reel deck; after all, I got into all this through taping.
Cheers,
DVV
