The thing about decks is that they age somewhat un-gracefully (I own about a dozen decks right now and used to work in a tape production house - GRT). They mostly need service and belts/tires.
Even direct drive decks will have slip clutches and idler wheels that harden and age with time. No matter what deck you buy, the odds are 50-50 that it will need service. Service runs from about $125 for a relatively simple (to work on) deck like a nice two head Nakamichi 480 to many hundreds if on a German deck with spare parts availability issues. That said, I would not own them if I did not like the technology.
The next issue is the tape itself. It ages and the internal (to the tape cassette) corner rollers and such get harder with time and drag on the now more brittle tape. One day - bingo, a favorite tape is toast. Oh Well - you got your enjoyment before it went. Tapes are like $.50 at the thrifts so this is a great way to get "vintage" music for cheap.
Now to the decks - My Denon 740 has the strongest transport of all the decks I own. It'll play a tape that others refuse to. That's playing with the devil, but what the hey - why toss the tape when I can get one or two more rounds. My Nakamichi's sound the best, but the Denon is a very close second. Especially on factory recorded tapes.
I generally say stay well away from dual well decks, so if any on your list are dual well - cross those off. The Naks are interesting, but I think the vendor is playing the price game, unless he'll warranty them? They Akai's are pretty bullet proof. They may not be as good as a Nak (not many are), but they mostly play forever and they have a large following due to their robust construction and that they do play well. Nothing taken away from Akai. In some ways they were leaders in cassette for years.
But if you want to buy one deck and don't want problems down the road, look for dual capstan three head direct drive models. MFG is not as important as this feature set. Decks built with these features were at the top of the respective MFGs range. They have the most robust drive/transport, best heads, best circuitry, etc. You can probably get one for around $75. Another $125 for service and you are in the door for ~$200 for a deck that may have cost $500-$900 new. It ran for at least 10-12 years before the drive parts started to age. Once serviced, it'll run that long again
