In the end, Post Master just isn't a very good game. It offers no challenge, no amazing tech-tree, has dated graphics and animations and a repetitive boring sound. Since there is nothing to keep you interested in the game for long periods of time, only a handful of people will actually become a Post Master.
If there’s one good thing I can say about Post Master it’s that it actually works. It’s not buggy, it doesn’t crash, and there is actually a game, of sorts, there to be played. I suppose the music's alright too. But all in all, it’s a sorry excuse for a game.