I've been using it internally within a lab environment, without issue. I should also mention that I never install the CCS feature set, which would probably be the only compatibility risk/concern. If you went ahead with production on SQL 2016, we would be able to help you as long as the issue doesn't boil down to something unexpected with SQL 2016. Without official support/certification for it, we can't be held to come up with a solution on the spot, for something we don't officially certify/support yet. Probably best to stick with SQL 2014 for PROD purposes, and wait for SP3 to do 2016. Just my two cents.