I still wouldn't buy one though - look at the DF review of the Core i5 7600K which at 4.8GHZ actually seem to have a weird performance profile in games:
http://www.eurogamer.net/articles/digitalfoundry-2017-ryzen-5-1600-1600x-vs-core-i5-7500k-review
Read through it very carefully. That Core i3 8350K will be similar performance to an overclocked Core i5 7600K. See how in more CPU limited situations it has worse performance but in CPU light situations it pushes ahead,which skews the averages.
Remember that is a 4.8GHZ Core i5 7600K too. Now consider the Core i5 8400 boosts upto 4GHZ - it most likely will beat a 4C/4T CPU where it matters.
I would get a Core i5 8400 or Ryzen 5 1600/1600x over the Core i3 8350K.