Nate - thanks for your feedback
Yes, FlashCache now has several generations of evolution under its belt and continues to optimize the performance of disk-based Unified FAS arrays. Our All-Flash I/O pipeline is so advanced at the moment that we don't need to double-buffer reads or writes via FlashCache to our SSDs.
OTOH - The main theme NetApp is conveying to the market now is that NVMe shows great promise when fully end-to-end systems will be deployed. Being ready at some of the App / OS / Hypervisor / Host / SAN / Controller / Shelf / SSD layers is helpful and enhances customer investment protection - BUT...
... It's very important not to overhype the technology today and underwhelm customer expectations.
If performance is a priority - independently audited and peer-reviewed benchmarks are the only way to go! :)