sometime i get wierd crashes while i'm modeling, and when I reopen the file it corrupts it (even with the autoback), and if i try making the same operation with an older version of the model it crashes, so at the end I have to export/import it into .3ds...
I don't think Photoshop has ever crashed on me. 3dsmax crashes are rare, but I have 5 autoback files saved at 3 minute intervals, means I hardly ever lose anything even if the whole computer decides to shut down for no reason.