Fist of all, Edmunds didn't let me choose the right truck model- LT Extended Cab 4x4 Long Bed with the 3.6L V^ and 6 seed auto. I bought my 2015 Colorado becuase I was tired of maneuvering my 2013 Silverado in town and getting just 15.5 MPG. The Colorado still has a 6 foot 2 inch bed, however it is over 15 inches shorter and 6 inches narrower than the fullsize pick-up. Just enough smaller to let the mid-size truck fit into normal parking spaces with some room to spare. The handling and braking are quite good and the 3.6L engine can make the Colorado move quite well, thank you. I drive the truck,not baby it and get very good fuel economy 22.5 mpg average in combined driving and up to 26mpg on the highway using 89 Octane gas. My single biggest complaint is the front seats. They are built for short, narrow framed occupants. Also, whey does a truck need a console mounted shifter to take up valuable space? A column shift would be much better. I am impressed with the build quality of the body. My Silverado was full of dash rattles and dour squeaks at just 15K while the Colorado has remained tight and noise free. The paint job could be better as it has some visible tiger striping in the metallic. This seems to be a common defect on GM's robot painted vehicles. The 4x4 system and Eaton locking rear differential provide very good traction and the traction/stability control works quite well without being overly intrusive. I removed the nearly useless rear seats to gain more in cab storage. Only children would fit back there and I don't have any. If you are planning on hauling more than two people-buy the Crew Cab. All things considered, I really like my 2015 Colorado and would buy one again. These trucks are definitely worth a serious look.
I needed to get a WT model rather than the base model to get the rear seats that are, at best, for occasional use. I elected to get the 6-cylinder engine because I felt that the 4 would be under powered, and there was just 1 mpg difference in fuel economy between the engines. I don't regret either decision. The Colorado is a great work truck, with adequate power, and it's quiet. I'm looking forward to getting years of use from it. Already, in the first year, I've hauled gravel, mulch, sand, paving stones, wood chips, and cardboard in it.
I also have used it on a week-long camping trip, after purchasing an air mattress that fills the truck's bed, a tent that fits over the truck bed, and another tent that attaches to the first and sits on the ground behind the truck bed. I really appreciated the driving position of the truck when I drove for 11 continuous hours to my camping destination. My actual mileage in the truck is around 20 mpg--a bit less around town and as high as 25 mpg for long stretches of Interstate highways.
Give this truck an extended test drive. Like the truck but HATE the seats. I have 18000 miles on this truck and it's been pure misury on my back and legs. I don't know what to do because I have invested so much money in this truck that I can't trade for quite a while. I have bought a cushion but that don't help much. Get lots of comments about the great looks. If they only knew.
The LT model with the premium interior/exterior and safety packages give this truck the feel of an upscale SUV. Additionally, the gas mileage of the 2.5L engine and 6 speed automatic transmission is great ( routinely 27.5 to 30 mpg highway) for the size of this truck. Update 8/23/16 -- After 6+ months of ownership I still love this truck. Yesterday my wife and I took our 2 grandkids (ages 9 and 12) on a 1 hour trip. Everybody was comfortable, Pandora entertained and the trip gas mileage was 30 mpg. The ride and handling is still terrific with great visibility and a big vehicle "safe feel" when traveling. Now all 4 of us prefer to take this truck vs our car for trips. I am still very impressed with this vehicle.