..the first watch is a "Pogue"; Seiko's (or Seiko fans rather) claim to a spacewatch like a Speedie. Lots of fakes and bitsas. Be careful.
Second is also fraught with difficulties. It is missing the plastic cursor for the slide rule function. Reproductions are available.
Third is a Seiko 5. I have never had one as I don't like the 5 logo.
In my opinion, it all depends what you are after. All are fun watches. The bezel on the 5 is cool.
Just make sure all functions operate. They can cost more to fix than to buy...
All that said... If you like them, who cares?