I am doing some tests. I was able to copy SDE FCs and Tables into a regular SQL server 2014 database using ArcCatalog. Now I can see these FC in SQL Server using ArcCatalog. It keeps the shape part. Also I was able to create an SDE view in SQL Server.
I can not copy Feature Datasets.
Then I copied back the FC created in SQL Server to ArcSDE and it seems ok.
I was wondering if I can use a regular SQL server database as a intermediate GIS storage for processing and then copy the final result into an SDE instance.
Any pros and cons.