Single tip would be less turbulent and less weight as well as less cost so I would hope they would do that.
Since the weight is very low and in the center of the car the performance gains will be in acceleration and braking more than handling so there could be a reason for some to spend the money more wisely elsewhere but for those that have already invested into most all else they can do for maximizing all aspects of performance, a very good mod
I spent many hours and a fair amount of money building what is likely the freest and lightest none Ti exhaust on a street driven FiST. I think it was around 24l lbs if I recall correctly, I would of gladly paid more than $950 for the Ti exhaust that might not flow quite as well(lots of little things took lots of time to make mine fit and flow so freely, it was a fun project) and save more weight!
I will be watching this for more info before signing on, hope I end up doing so