Tiny datasize with long refresh time OR Large datasize with short refresh time?

What is better in terms of costs:
 

Scenario A) To have a smaller dataset (250 Mbyte) but having longer refresh time (15 minutes) for the dataset in PBIS.

Scenario B) To have a larger dataset  (544 Mbyte) but having short refresh time (5 minutes) for the dataset in PBIS.

The refresh of the dataset will be done once in a day.