Explanation
It is better to use a clustered index.
Columnstore indexes are the standard for storing and querying large data warehousing fact tables. It uses column-based data storage and query processing to achieve up to 10x query performance gains in your data warehouse over traditional row-oriented storage, and up to 10x data compression over the uncompressed data size.
In SQL Server, rowstore refers to table where the underlying data storage format is a heap, a clustered index, or a memory-optimized table.
References: https://docs.microsoft.com/en-us/sql/relational-databases/indexes/columnstore-indexes-overview