I've tried backing up to my iDisk and to Amazon S3. Twin uploads some files and then crashes on both my iMac and my Macbook Pro. When i relaunch Twin, it has no ecord of ever starting the backup, so I have to first delete all of the files from iDisk that it previously backed up. I have yet to get a successful backup of my Library directory on my iMac after 5 tries. I submitted a request for technical support and I am still waiting for an answer after 3 days. I called the company and was told that they are a French company and many support technicians are on vacation! They also refused to refund my purchase.