Dot Net Remoting

Since our web server is not allowed to install Microsoft Office, I am going to use an application server to process Excel objects. The web server will then call this remote object.

Design considerations:
a. to remote only Excel portion and pass in dataset from web server? or

b. to remote the entire Controller - i.e. from extraction of data to excel formatting.

I am inclined towards method A as I will not need to have two copies of objects for data access. Disadvantage of method A however is passing of dataset to the application server. I am not sure whether this is the most effective solution.