Yeah there's some good value buys for overclockers to exploit. However, it seems there's little headroom beyond what the tops models are clocked at. That ~4.1 result was on high end mobo and watercooling. The hype-driven segment of the community (probably just a few loud people but we've all seen these posts) which has been speculating ~4.5 Ghz on aircooling is going to be disappointed.
Maybe why AMD has been packaging 500g beefcake coolers here, these chips have been pushed to beat everything in Intel's lineup.
To stay in perspective however, Ryzen doesn't need to hit 4.5 Ghz to impress. 8 cores at 4 Ghz is pretty fantastic to be fair

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**Possible that some later steppings improve OC-ability

. Being AMD64/Opteron OCer from back in the day I have observed certain steppings/batches to OC 500 Mhz better than others...