The Scorpion is a good step up from the OEM system, as is the Cobra system too, both are well made and fit without issues, and neither are too disruptive in the cabin, very easy to live with daily for long and short journeys.
Always worth adding the Y pipe, as the OEM ones tend to fail on the flexis, we've seen more and more suffering when we've had them in the workshop.
I would go for the Cobra Sport resonated, as this seems to fit the bill on the above, and you can also add their Y to the system too, which keeps everything consistent...