My Mom doesn't have the XT, but a 2015 2.5i Premium with the All Weather Package, and we've got a CX-5 Touring as our family car. I've also got a 2006 WRX STi, so I can give you a pretty feel for Subaru.
Turbo Subarus are very finicky. I know the FA motor isn't the EJ series from yore, but all Subaru are extremely picky with oil. Last I checked I think they were asking for 0w-20 for the turbo cars, which is a recipe for disaster.
That being said, the Forester is MUCH better on outward visibility than the CX-5. It's one of the main areas I felt the Subaru excelled compared to the Mazda. When you sit in it, the greenhouse is very tall and airy, and doesn't have that high sill feeling you get with most new cars. I will be curious to see how the Mazda's interior materials wear, but they have a higher quality feel than the Subaru. Unless Subaru has upped their quality in the past few years, the interior materials will wear faster than you expect (I am shocked how easily scratched my STi's HVAC console was scratched. I purchased it used with 16K and there were many fine scratches around the knobs). The Subaru has a decent amount of torque from the 2.5i and the CVT didn't bother me all that much, at least compared to my Mom's Rogue's CVT, which was painfully awful to drive.
The Subaru is noisier than the CX-5 on the highway in terms of tire noise and overall cruising. I've heard the 2016 CX-5 has more sound insulation than the previous years, so that might play a role. That being said, during initial startup and acceleration, the Subaru is quieter. I'm actually surprised the Mazda has as much growl as it does. It doesn't necessarily bother me since I have had loud cars forever and I do enjoy it, but it is a point to note. The CX-5 is more fun to drive than the 2.5i Premium, but I suspect the XT has a more sport tuned suspension. If not, a quick stop at Cobb Tuning or Whiteline/RCE and I'm sure you could have some real fun in the corners. I actually think most of the STi's suspension will bolt up to it.
The turbo models are pricey compared to the NA. I found that the NA Forester was significantly cheaper per content than the CX-5. My Mom's was approximately $3,000 less than mine, came with a much larger sunroof, heated mirrors, seats and wipers and roof rails and currently gets 1 MPG better combined (although our CX-5 isn't broken in yet). We have the leather wrapped steering wheel and Bose system, which does sound better than the Subaru's base unit. Neither model has navigation, although the Mazda SD card would be a cheap upgrade.
Depending on your preferences and the deal you can get with the XT, I'd almost be tempted to cross-shop the new CX-9 turbo.