Kendra Little exposes a gotcha with non-clustered columnstore indexes and computed columns:
Looking at the execution plan, SQL Server decided to scan the non-clustered columnstore index, even though it doesn’t contain the computed column BirthYear! This surprised me, because I have a plain old non-clustered index on BirthYear which covers the query as well. I guess the optimizer is really excited about that nonclustered columnstore.
Kendra links to a Connect item from Niko Neugebauer to add persisted computed columns to columnstore indexes.