Niko Neugebauer clears the air regarding memory-optimized columnstore tables:
I would like to dedicate this blog post to the Memory-Optimised (also known and LOVED as Hekaton) Columnstore Indexes and their limitations in SQL Server 2016.
Disclaimer: the Memory-Optimised Technology is the ground-breaking development, which will be truly appreciated only in the next couple of years, and it has its incredible use cases (and maybe I will be blogging more about this space in the next couple of months), but people needs to understand that mapping InMemory Columnstore Indexes to disk-based Columnstore Indexes 1:1 is a very wrong idea, and that because InMemory technology is significantly younger and less stable than Columnstore Indexes – there are some very significant hidden cornerstones.
It’s important to read this post as “this is not yet a fully-mature product” rather than “this will always be worse.” But it’s just as important to understand the limitations of the product and not think you’re getting something that you aren’t.