Hi. As a new user I'm in the throes of setting up my new MBA. Time Machine. 1. Do you use this and how good is it ? 2. I have the 128gb MBA so what size external harddrive size would suit. Could I use a USB data stick ? 3. Once a backup is done will I need to do anything else. Ie do any future backups on a regular basis or just keep the 1st backup safe just in case something occurs. 4. If I choose not to use time machine and my system has a failure will I be still able to do a clean install from apples website and just lose my data from the SSS drive. Sorry for the noob questions but after searching on google etc the infos not clear to me !