I may be wrong but I believe that mars hydro dont give the same spectrum of light as the spider farmer or even the viparspectra. It may have been the model I was looking at but if I remember correctly it didnt give off UV. It may not be UV it could be something else but it was mentioned on the spiderfarmer' info. It promotes rapid growth.
I think the mars draws more power with a very similar light output also.
Reflector or no reflector your plant isn't going to be getting any extra light just because it has one, the figures included are with the reflector obviously lol. Look at the light output figures, power draw and the cost of the lights and that will be your best light. Everyone has a different opinion on it.
I decided on the viparspectra because of the price and the SF gains were marginal and I personally couldn't justify the extra cost and I'm having great results so far!