Actually, if it was in fact 150' tall, had the same length of track as SUE, and went 70mph, it most certainly would launch off the track (or hit the plunger extremely hard). One of those stats is incorrect. If it's truly 150' tall (which I HIGHLY doubt it is -- why on Earth would Intamin design this custom when it's an off the shelf model) then the speed would be around 60-65mph. If it goes 70mph, then in reality, the towers should be close to 180' tall.
Suffice to say, IMO, I would bet the farm that all three US Impulse coasters will be exactly the same height, the stats are just coming from different marketing departments.
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If you are looking for trouble, you found it. -- Steven Hawking