First things first, Super chips is a very reputable company, been leaders in the chip tuning business and i know of them since i knew about chip tuning and have used them in the past. If you go to their HQ in Milton Keynes, they will even dyno the car for free alongside the tune.
Secondly for an NA car, unless there are specific restrictions like for a mazda 3, the same car comes in 2 states of tune a 120 BHP and a 165 BHP and the throttle cut off removal really unlocks the extra power. For a turbo car, its a different story and the gains with just a tune are noticeable.For a GT86, there is no such restriction and for the hardware it comes really well tuned. With a superchips tune you will not gain much.
The ECUTEK gives you all fancy features like flat foot shift, launch control etc, which people rarely use in daily driving.
So in summary, for our cars a NA tune without hardware changes (like manifold) is not worth it as the gains will be rarely noticeable.