With a rare breed like the premier 2015 Mercedes Benz GLA 250, it's hard to make assumptions about its driving dynamics. Well, you know what they say when you assume, anyway -- and if you don't, well, you'll just have to look that up yourself because this is a family-friendly blog.
Anyway, the crossover/hatchback fusion that is the GLA 250 offers the best of many worlds when it comes to cargo capacity, passenger accommodation…