I would recommend some sort of amplifier-cabinet simulator, or a multi effects unit that includes the amp/cab sim. The guitar itself is only half the equation when it comes to sounding like an electric guitar. Both amps and speakers are specially voiced for guitars, with an accented mid-range, so both analog and digital simulators try to emulate that. A sound system is designed for general music, movies, and uses the full range. So yeah, try it, it won't sound bad, but it'll possibly not sound as good as it does through your amp. If you're curious about effects anyway, check out a multi-effects unit, like I said, because it would allow you to play through that sound system, as well as going straight to the mixer in a gig or rehearsal, and it would also get you some effects to play with.