Design Query

I have a design query. I have the following design and want to know if it is ok or not.

I have 2 datasources. DS1 and DS2.

DS1 is full and DS2 is delta based.

Datasources are connected to a DSO which is set for overwrite.

I want to create a cube on top of dso.

My question is: DS1 will alway bring in the same load (if no changes are made) how would it effect on the load going to the infocube, would it make keyfigures append?

Please let me know,

Thanks.