The battery life of the 5700 is an issue, because of the EVF, and focusing in low light conditions is really a problem. There's no AF assist light, and it can't utilize external flash AF-assist, so there's nothing much you can do about it. To make things worse, manual focus SUCKS, because you can't see a thing through the EVF. Upping the ISO will help a bit though, but well... it's one of the reasons why I sold it.
If you do alot of shooting in low light situations, forget it. Get the G3. Otherwise, it's a great camera. Check out my galleries.