I've had about 2/3 Speck cases for my Retina Macbook Pro and they weren't really that good. Seems to be a good quality and feels nice on the laptop at first, but all of them chipped / cracked quite easily with normal transportation (never dropped or mishandled and kept in a Tumi Laptop backpack) especially if you remove it periodically (as you should) to clean the laptop and make sure there isn't an excess of dirt / dust caught in between.
With my 2016 15 inch, I browsed Amazon and came across a brand called Kuzy which has far better reviews than Speck does (not to mention the price was just about $20 in comparison to Specks $50) - so far, its been just as good as Speck, and has yet to crack or show any signs of wear and seems more durable. Even if it does crack in the near future, I would have spent $40 for two cases (available in a wide variety of colors) in comparison to $100 for two Speck cases.
Take a look on Amazon and see what they have available and read some reviews to see what best suits your needs.