We have a 2015 Terrain SLT(one step down from a Denali) with 42,000 miles and really like it. It has the 2.4l with AWD which can be a bit of a dog but I tuned the ECU and it surprisingly quick when your foot is in it. It is fast enough for my wife who crusies at 80+ mph and survived many miles out west in the mountains spending many miles at 5,000+ rpms and was never without power.
That 6,000 mile trek had us and the dog very acquainted with the Terrain. It is a little more roomier than the Envision Premium ll which we picked up for $35K with 3,000 miles to replace it. If the Terrain had the 2.0T from the start we would probably would have purchased it outright as she likes the boxy shape. She is not to keen on the 2018 Terrain as it lost it's individuality. I personally do not like the stiff front seats in the Terrain and think the stiffer springs make it more truck-like. But I'm coming from Buick Verano/Encore and Cadillac ATS/XTS. The GMC has to play a middle ground to the SRX at the time and the lessor Chevrolet Equinox.
Funny thing is I let her take the Envision when I was changing the oil and rotating the tires after the trip out west. She gets back in the Terrain and ask why her car rides so bad and asked what I did to it. She got used to that Buick ride and it does ride good.
We just had my Dad out for Father's Day and was showing him how the Driver Confidence Package allows the car to steering between the lines. He was impressed. We were commenting on where to go for desert and said we should avoid some construction areas due to construction and and rougher roads. My Dad pipes up and says the rough roads wouldn't matter in the Buick it rides so well.
As you can guess the Envision has a rubber mounted subframe and really floats over the railroad tracks near work. The hyperstrut front end(with AWD) is very direct and much more athletic than most everything in the sub-$30,000 range. We rented a 2017 Ford Escape SE AWD to drive 450 miles out of state to pick up the Envision and I couldn't wait to get out of the stiff, foam seats. I thought I was going to end the 7 hour trip with tinnitus it was so noisy and the steering so bad. I love the calibrating they did to throttle input and smooth transmission tuning we averaged 32.3 mpg with the cruise control set at 65 mph. And like the soft headrests. But it had me wondering what Ford does to pull the Lincoln MKC that many have raved about.
I'm averaging about 25 mpg on my 8 mile commute of half highway/half city. Best 25 mile average was 30 mpg. The stop/start works well and is non-intrusive. We have 5,000 miles now on it and love the electronic nanny's as they work well. The rear climate control is nice with it's vents the Terrain doesn't have. I can also control the rear seat climate from the front too.