If you want to download or stream media with Use-your-Drive, you will stream the files directly from Google Drive. So there are no bandwidth or file size issues for your web host. Only when you download zip files, these files will be downloaded to your site and can generate some traffic.
Google doesn't mention any bandwidth limits for Google Drive, so they probably have a sort of 'Fair Use Policy'. Keep in mind though that there are storage limits on your account (which you can upgrade at any time).