yes this is a good deal. i personally like the single monitor version better than the 2 monitor version, less to keep running, but i would jump on that one! ed
I just bought a Playchoice single monitor last week for $450 -- but it had more than that in games inside.
I would just try and determine if it's hacked up inside (switcher PSU, etc), what the games are and overall quality of the cab. That said, I suggest doing it all the checking onsite because if your area is like here, it may not last long at all It looks pretty sweet to me.
Expect to do a capkit etc. at some point if it has not been done already.