One final method...the "my name is Raven, I am a moron" method. It is very effective.
If you have enough room, simply save your progress EVERY SINGLE TIME you make a change. Save it to a different file, like David1.max, then David2.max and so on.
Now I save every stage of the models development, but you dont have to do that. It allows me to go back as far as I want or need to...sometimes the direction I go is all wrong and I have to go back about 6 or 7 steps, or maybe want to use a piece of a prior version in the current mesh.
Since I am a professional idiot by trade (closed max many times when I had not saved my work) as well as having to deal with corruptions, both this method and Max's autoback prevent loss.
Of another note, I keep both DVDRW disks and a seperate external hard drive that I back up my work to periodically using the program Compare and Backup. Keeps the process simple.
Just some things to think about.