[UtVgG] Is this a fair deal?

I have a chance to trade an Asteroids for a Berzerk. The Berzerk is claimed to be "minty" but not working. The guy says that there is a chip missing on the board, but everything is there. So, assuming that I can pop in a Z80 (or whatever the missing chip is) and have it come up, and that the machine is in nice shape, is this a fair deal? The only reason I ask is that I don't really like Berzerk and after I played it for a week I would want to trade it off or sell it. Normally when I trade games the only thing that matters is "Do I want this game more than that game". I feel cheap trying to assign "value" to a game. Any opinions? Sean McLachlan MIS Manager LithoFlexo grafics inc. 801.484.8503