The GT Sport got the 2.5 petrol turbo, whereas the Exclusive Line gets the 2.0 petrol normally aspirated.
We’re currently running a 2 litre petrol turbo in the Volvo, so I’d expect the slightly larger size of the CX-5 to offset the fact it doesn’t have a turbo, and so mpg wise it wouldn’t surprise me of running cost of the 2.0 CX-5 was similar to the Volvo.