I have a 1964 Rock-Ola Princess Royal. It took a fair amount of work to get it going, but since then it's been fairly reliable. I still need to rebuild the amplifier though, as it distorts some high frequencies. A juke of this age definitely will need some work, but I like this one for several reasons. For one, you can see the record playing. That's something that a lot of the newer jukes hide, but it's fun to watch. It's also not very big, which is important for a small gameroom area.
Another interesting feature it has is the ability to play 7" LP's as well. That format is pretty useless at this point, it was a jukebox-only format that never took off. But, the great thing is that this gave this machine the ability to play records with either the large 45 RPM hole, or the small LP center hole. The spindle has little tabs that stick up to sense the size of the record. A small hole record pushes them down, which flips a cam and changes the speed to 33 1/3. I simply removed the cam, disabling the speed change. This leaves me with an automatic center spindle, allowing me to play European import 45's with the small hole unmodified.
But, again, on a machine this old, be prepared to do some work on it when you get it, unless it came already fixed up... It also only holds 50 records.
Also, when you do get your jukebox, you're going to want this:
http://www.pinballrebel.com/archive/other/onlinestrips/index.html
It's an online title strip generator. Just type in the records and it'll generate a PDF you can print to make title strips for your jukebox. Use cardstock for best results.
-Ian