i always thought the reason the TT tank was so expensive had to do with the FI (the pump or something). so (going by my logic) anything besides an auxiliary tank that feeds into the original tank or expanding the original tank itself wouldn't necessarily work would it?
plus at 60mpg max kools tank would get you a 260 mile range.
in my opinion it's the best option right now, and it doesn't add to the weight of the front.
"Open up your mind and think like me." Jason Mraz