The toolkit can work for simple scenarios. I just used it to import a series of blogposts into a site. The only caveats with the tool are that it can't write into multiple tables, at least from what I have seen. If your module is a simple table, then you would be fine to select the excel file and run through the wizard. If it is connected with other tables and is more complex, then you will have to create a simple import tool and parse the excel file to get the nodes and data that you want. The tool should allow you to select a file when you get past the first couple of screens. After that, you map the fields to your data structure and import. Just make sure you back up your files first and database, just to be safe.