ATI Sunpower for a 120g

Will a 6 bulb 48" ATI Sunpower be enough light for a 4'x2'x2' SPS dominated tank? I don't need the entire tank lit (this should help prevent algae from growing on the glass). My main concern is if the 6 bulb will be strong enough for the 42"x18" area that I need lit for 90% SPS corals and 10% LPS corals. My other option is to stick with what I have (Two 250 watt MH's and two 54 watt T5's) or wait for the new 8 bulb ATI Sunpower to release in one to two months. I saw a 6 bulb ATI Sunpower at the LFS and the light spread from front to back isn't great, the 6 bulb fixture is 13.5" wide and will probably only give me a 15" width of good light coverage. I really don't want to use the 8 bulb because bulb replacement will be as much as what I currently have and the power usage is creeping up to what I use now. On the other hand, the acrylic sheild and the metal exterior of the Sunpower was cool to the touch when I saw it, this is a big plus! If anyone has pictures of the ATI Sunpower or ATI Powermodule over a 120 gallon tank please post your pics.

 

According to Reef Geek the Sunpower is good for SPS dominant up to 110 gallons. I think that would be close enough.