Quoted from ASOA:
YES. Please listen to this post. It will save you a lot of aggravation in the future. I'm sure you can buy the other one but If the people had the option back then they would have chosen the new board system. It is referred to as light system 2.0 and they have upgraded the computer and IO board as well. Late model WOZ will have this new system. I own a 2.0 system WOZRR so I can tell you my experience and experiences of others that have had the earlier set up.
Bottom Line WOZ is a great Game Very deep and beautiful game. Congrats!
Im not going to yell at you for these statements, that has already been done. What I will say is that as JJP Distributor who has been on board since before woz was being shipped I can tell you that yes, there were some issues. That being said, my personal ecwozle was built in 11/13 and I have never had an issue. As the old saying goes "a happy customer will tell 10 people, and unhappy will tell 100." We hace heard from those with issues, but i would be willing to bet that there are many, many more happy customers that we dont hear from. My game has gone to countless shows, tournaments, in house parties, etc. It has 1000's of plays. No issues at all with light boards, monkey, playfield, anything really.
For the op, if you are worried about a game not working, buy a new one with a warranty, otherwise it's pinball. It is going to break at some point. Find a local distibutor (or not a local one, but one you trust) to work with to help you if there are issues. Most of the bugs have been worked out of the orginal light boards. The 7.5 boards are not nearly has prone to failure as the earlier versions.
If you (op, or anyone else reading this) would like to talk more specifics then send me a message.