I'm thinking about getting a compound crossbow but the major thing holding me back is re-stringing. Barnett says something like their strings last around 200 shots, so does that mean after every time I fire 200 shots I need to send it off for re-stringing?

Unfortunately compound strings can't be guaranteed but if you take care of them they can lost a long time, we very rarely have to re string crossbows we sell and we have been in business for over 6 years.