Assuming you got a complete copy of the game, $10 is right about it's value. Moving on from that part of your question.
PSO Remains to this day one of my most favorite games of all time. By all means, do play it. The play style will take playing for maybe an hour to really get use to not just the play, but how the third person camera view works. Once you get the mechanics of it though it is absolutely fantastic to play.
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