When these were launched in 2010, they were leaders. A significant improvement over the old Equinox/Torrent siblings. They were the quietest, yet most efficient (with the 2.4L). They also had more room and refinement. Their primary competition were the RAV4 (which, in four cylinder spec had a 4-speed auto), the CR-V (which had a five speed auto), and the Escape/Tribute (which were an ancient design), so the 2.4's acceleration was fairly competitive. But now the segment has moved forward with some great new vehicles (the third-gen RAV4, the CX-5, new Escape, Forester, I could go on), but these haven't had any meaningful updates (besides the 3.6L in 2013, this refresh hasn't done a whole lot) and have moved to also-ran status. Still more competitive than bottom feeder models like the Patriot/Compass and the Outlander, but not where it used to be. In fact, you can tell the dated design of the Terrain when cpmpared to the new 2017 Acadia. Makes you wonder what's the point.
Having said that, it'll be interesting to see what they do with the next-gen 'Nox/Terrain when the redesign is unveiled (probably late this year/early 2017). Using the Cruze platform and dropping the weight, as well as sizing it smaller should make it a more competitive choice.