I'll preface this as stating I am not a gem snob and truly do not care what people wear. My wife and I went with a moissanite and we're perfectly happy with our decision for her engagement ring, and will probably buy more moissanite in the future.

That said, when it comes to cubic zirconia the stone will definitely scratch with regular wear over several years. If you see a clear stone with scratches, its obviously not a diamond/moissanite and probably cz. To a careful observer, its also not incredibly difficult to tell the difference between diamond/moissanite/cz with the right lighting. Cubic Zirconia lacks the refractive index to really match the brilliance of a similar diamond/moissanite.

Ultimately though I fully agree with the idea of wear whatever you think looks good.