Excellent vehicle, all around. Sure, it has some weaknesses, but through and through this thing is an impeccably built tank. I've waited awhile to review this small SUV until living with it for some time (not quite 2 years now). I've previously owned Lexus, Saab, and several BMWs. The GLK demonstrates what Mercedes-Benz is all about, and this is (was) their 2nd least expensive model -- bodes well for the more expensive lines. I've had exactly one problem with the car in nearly 25,000 miles; a failed wheel bearing that the dealer had only ever seen twice before on the GLK. Let's not discuss how many times my SAAB saw the dealer in 25,000 miles, nor the BMW for that matter.
Solidity. Cruise control that keeps you where you tell it (i.e. 50MPH means 50MPH -- even when going down hill, it breaks for you and doesn't let the car "run away" like most others do). Durability of the MB Tex seating, looks and feels just like leather but mine shows nary a sign of aging. Our 2011 Volvo XC60 with full leather seating shows wear in just 20,000 miles. Cornering lights are very useful. Xenon headlights are probably the best of any car I've ever driven. Turning radius is killer, I can flip around anywhere without needing to make a 3-point turn. Super easy to parallel park in the city. This will not be my last Mercedes-Benz, super impressed with the brand and their vehicles.
Nothing new here: gas mileage is fair (yet rectified in the 2013 and newer models). The 2015/2016 redesigned GLK needs to incorporate a little more legroom for rear seat passengers, as well as better egress/ingress. Bluetooth audio streaming should be available on this vehicle being that it's a 2011. MB needs to work with Apple to better integrate the iPhone. While it's not bad, it really isn't great either. A Honda Civic likely has better tech in this category.