I have had my WOZ machine for just over 1 year. In the year of ownership I have added some mods such as tree eyes that illuminate with pop-bumper operation, castle walls, tornado, lollipop rainbow targets, cliffy protectors, illuminated winkie drop target, some extra lights and other stuff.
Definitely enhances the game and in the case of the winkie target helps play as it is easy to see when the target is up or down.
I have had some switch adjustment problems, LED lamp board problems and the ball lock relay problem early on with poor solder joins on the coil plus some adjustments within this year of operation. One switch associated with the Wizard hole -- an upright switch behind a stationary rubber was difficult to find, until I associated the sound correctly to that specific switch. At times
during play the switch would hit making the sound occasionally until it become all the time and very annoying.
Multiball brings unusual situations, such as trapping two balls behind the upright winkie target making for interesting play until the target drops. Two balls in the Crystal Ball sometimes causes
the VUK a hardship.
No major problems causing a raise in blood pressure -- although early on the LED boards were a concern. As I have an early machine, my LED boards continue to fail, although at a slower rate.
So after one year in home operation I feel - my opinion, that the fundamental design is working solidly with the firmware design. Problems seem to be common pinball problems at this point.