The Mars TSW2000 I think is the cheapest light that will cover your area somewhat adequately.
The SF and VS are better lights, but the difference is just a slightly more efficient LED. You will not get better results with them, but over the course of 3-5 years, the energy cost offset may balance with your initial investment.
The takeaway? If money ain't no thang, get the VS. If you'd rather save some money, get the MH.
When comparing these lights just realize: the more watts, the better. The VS is 240w and you would need two to cover your space in flower. The SF is 200w and you would need two again. The MH TSW2000 is 310w and one would be sufficient although I use two of them in my tent which is the same size as yours.