Wide Angle Lens: Olympus 9-18, good for night handheld?

I am looking for a wide angle lens and wondering if the Olympus 9-18 will be a good choice. It has the largest aperture f4 and wondering if that will be okay for night handheld shooting?

I thought about the Olympus 12/2, but it lacks of the versatility on the focal range and a bit too pricey.