They all need work of some kind. The wizard-o-wor,gyruss,and kangaroo need monitor kits (or a replacement chassis), or a new monitor. Figure $5 for a cap kit to $100-200 for a complete monitor. I found a site with replacement chassis for like $65.
Ok- I went and found the place here I never dealt with them, just found them.
It's an easy swap, I could do it if someone wanted.
The gravaitar is different breed of cat. It's a color vector monitor (read obsolete) the monitor just quit while running. They may have new technolgy now to replace a vector monitor, I havn't paid attention in some time. It is a gorgeous cabinet, way cool looking, I'd be tempted to put a pc running mame in it.
The battlezone runs fine till it warms up, then starts resetting itself. This is another nice looking cab.
I can take some pics... ;\)