Nothing is likely visibly broken but there are things that can go wrong over time.
Captainscott sent me his Super Mario RPG cart which you can read up on his problems with here:
http://digitpress.com/forum/showthread.php?t=155527
I'm testing it right now but it looks like I've managed to restore his cartridge to factory fresh. Boots up each time I've tried it and my brother is playing through to the first boss fight after leaving Bowser's castle. There wasn't anything visibly wrong with the cartridge but that is normal. All it took was reflowing of virtually every solder joint inside the cart, a bit of cleaning and the swapping of a component for a new and higher quality version.
If you'd like a professional to look at it I'd be happy to.
