Comparing the benchmarks of the Ryzen 5 1600X and the Core i5-7600K, we concluded each one has advantage in some applications and disadvantage in other ones, so we can say the they at very similar processors.
In applications that use a big number of threads (like Handbrake, for instance,) it is clear that the Ryzen 5 1600X is faster than the Core i5-7600K, which has only four threads.
In games, on the other hand, there was a small advantage favoring the Core i5-7600K, which was a little faster in eight games. The Ryzen 5 1600X reached a higher framerate in two. Besides that, it is clear that both CPUs are great choices for gaming computers.
A plus of the Ryzen 5 1600X is its good overclocking capability. On the other hand, the fact it comes without a cooler is a disadvantage, even more because high-end cooler compatible with AM4 socket are still hard to find. This may, however, change in a few weeks.
So, we can say the Ryzen 5 1600X is a CPU with excellent cost/benefit ration, mainly in programs that use its twelve threads. In most games, however, it is a little behind its competitor Core i5-7600K, being still a good option.