I have 10 minute interval Autosave running here. I never notice anything happening in the background. The only time I know there is Autosave is when I need it, which I never do since I never crash. I just asked a client I’ve been working with consistently since May if they remember any crash in the long days we have worked. They don’t, so it’s not just my imagination. I can’t remember the last time I opened a .bak file.
But there is always a list of .bak files so I know it works. So transparent, I forget it’s on. I’m on Win 7 x64 on a new, fast PC. Overclocked i7 4770K with 16GB ram. Don’t know if that’s it or not., since I don’t know what system you are on. But I haven’t noticed Autosave at all since I built this machine.