continuous servo limitations

Hello and thanks for checking out my post.

I'm relatively new to using the arduino and have no experience using a servo, so I was wondering if someone might be able to explain the limitations of using a continuous servo. The project that I'm starting will be raising and lowering an object attatched to a spool of thread attatched to the servo. I'd like the user to

A couple of high level limitations:

Speed: Servos arn’t fast…

Control: It’s hard to control the servos. You dont actually know where the servo is. It’ll be a case of gestimating travel.

Beware of stalling the motor in a servo. Some servos have gears inside that can be damaged by stalling, and I think it’d be more likely to happen with a crane-type mechanism that you mentioned (when the load reaches the top).