Moissanite is not an imitation diamond. It is its own stone, silicon carbide, and it throws noticeably more coloured light than a diamond does. Under a restaurant light a moissanite flashes rainbow where a diamond flashes white. Some people want exactly that and some people do not, which is the only real question worth asking before you choose one.
It sits at 9.25 on the hardness scale against a diamond's 10, so it takes daily wear without trouble. It also costs a fraction of a lab diamond, which is why most of the oversized centre stones you see below are moissanite. We cut it in colourless DEF and near colourless GHI, and in champagne, grey, green and deep blue for anyone who does not want a white stone at all.