I drove an EX with Sensing last weekend and a Touring today. The only difference I really noticed in the engines was the turbo seemed louder under when accelerating moderately. But I wasn't really looking for engine differences.
The cloth and leather seats are both better than my Accord's.
The steering is so much better than my Accord's. The quick ratio makes it feel more precise, and it's really really noticeable making a U-turn. Overall I liked the feeling of driving it a lot more than my Accord.
Something I noticed that I haven't seen mentioned was that the ACC set speed flashes if it's set more than 10MPH over the speed limit of the road you're on. It was really accurate, too. I got off an interstate where I'd had it set at 70. A car was in front of me so I let it follow them all the way down to a stop at the end of the ramp. I didn't notice it flashing then. When I turned onto the surface street (40MPH limit), I hit Resume. The set point went back to 70, but it was blinking. I played with this some more and like I said, it seemed to start flashing once the set point got to 10 or more over the speed limit. Pretty cool. I should've tested to see if the speedo or something would flash if I actually did go over the speed limit.
I didn't notice whether the EX did it or not. It might only be in cars that have the navigation system.
I see what people mean about the ACC being kind of jerky when slowing down. I hope a software fix will come out for that. I also wish resuming the ACC set speed would try to match the acceleration rate of the car in front of you. It accelerates kind of leisurely, even with ECON off, which I could see resulting in people constantly cutting over in front of you in heavy traffic.
One thing I really liked about the ACC, though, was that it doesn't dive on the brakes if someone cuts in front of you as long as they're going your speed or faster. The 2015 Mazda6 I had was terrible about that.
I really liked the Brake Hold feature a lot more than I'd expected to.
One really minor gripe is that holding the steering wheel volume button up or down doesn't register as repeated clicks. I know you can swipe for that, but I'm used to holding that rocker for big adjustments in my S2000 so I wish they'd made that an option too.
The 450 watt system is better than the garbage that's in my 2015 Accord LX, but it's still pretty crappy.
It's really weird if you start drifting to the edge of your lane before putting on your signal to change lanes. You feel the wheel fighting you a little, then you feel it let go once you put your signal on.
I like that the icon on the dash shows you whether the car can currently detect where the lane lines are or not, so you can know whether to expect it to do its thing or not.