I tested it with my super sensitive butt dyno last summer in the middle of July. I think temps those days were over or around 100 F. I was not interested much in numbers, as buttom line was how car feels after traffic, how far back I was falling behind my friend's M3 (stage I those days) compared to winter months ( I first installed chip ). Also, Subaru and other engineers already did the homework, so I don't have to proof anything here.
I am not on a budget, just think it should not cost that much for "intellegent" spray system. It is too fancy, and I think unpractical. You will run out of water in big city traffic in first 10 min. Benefit is not there to justify the price. So, goes for oil cooler for stage 1-2+.