Neither. I shot the photo in color. Changed it to B&W, adjusted the levels to make it appear at dusk, then added the lens flare in color in Adobe Photoshop.
The idea is good and worked fine, here, I think. All the photo now needs is a crop from the top righthand corner, so you loose some of the sky and some of the open water (the photo can live better without it, I think). That would put the lighthouse out of the centre and give the added light room to shine into, you understand?
personally I don't like the fake flare at all. Looks too out of place for me. I'd personally crop it portrait like Eric said, and get rid of the flare.