>I have downloaded the XFRX demo. How can I use this now to generate an Excel file within my app so I can the management to purchase or not.

We use XFRX extensively to generate our "to disk" reports. While it will indeed generate your report to an Excel spreadsheet file, we had to remove this option from our application because the resulting spreadsheet was impossible to edit for our users. We have very detailed reports, it's a tax application, and the text fields are right next to each other. XFRX will generate cells for each field and although the resulting spreadsheet is a true representation of our report, our users complained because it was very, very difficult to edit the data in Excel.

If you have relatively simple reports, XFRX should work great. Our experience with the product has been excellent.