Time Machine is a very cool application. I can use either a USB external hard drive, or use a time capsule. It will automatically backup my data, and with my backup drive attached, I can view and restore my backups in an AMAZING UI (user interface).
But as I realized the first time I tried to use it, there are MANY downsides.
1) To backup using time machine, I need my backup drive to be twice the size of my internal Hard Drive.
2) It gets unhappy with FileVault. Apperently, I was told that you should never have FileVault on anyways by an Apple Genius at the Genius Bar at my local Apple Retail Store. then why do they include it in OS X?
3) You can’t use it with network drives.
And heres a heads up. If one of the first things you did when you got your new Mac was turn on FileVault, and you have used up ALOT (I mean around 80 GB of a 160 GB hard drive (internal) then it will be impossible to turn it off. You will have to move or delete about 10 GB from your hard drive To turn off FileVault.
Moral: Keep your Hard Drive uncluttered, and ORGANIZED!
I went and tried My 200GB hard drive with Time Machine, and I have a 160 GB backup drive. When I try to backup, it said I needed to have a whole 300GB on my backup drive. I gave up at that point and started running in circles wondering what was wrong.
Answer:You need to have at least twice the size of your internal hard drive on your external backup drive (in this case, my backup drive would have needed to be at least 320 GB).
I go to do a backup and Time Machine is messing up. it is unable to interpret how big my home folder is.
Answer:Turn off FileVault
From those, you can probably tell that Time Machine is incredibly specific about the things it is happy about.
Conlusion: Time Machine overall is a very good product. It jut depends what conditions it is working in, such as cluttered, or encrypted.