Almost a month later, and I still really like the i440D Slate PC. But, for weeks I have suffered from the Vista i440D hanging when I try to put it into sleep mode. Repeated internet searches, calls to Tablet Kiosk, etc. did not help. I finally started over with a software re-install to determine which program causes the issue.
I have determined the i440D Vista's sleep works fine - except when Windows Live One Care is installed. If One Care is present, the sleep function just won't work and causes big problems. My other two Vista tablets' sleep mode works fine with One Care, and this is the only problem I've found with One Care on the i44D.
So, if you are having sleep or hibernation trouble with Vista, and have One Care installed, uninstall it and see if that helps.
Note, this is the Vista sleep problem where the PC hangs and has to be turned off by force - not the Vista sleep problem were the PC wakes up on its own, or the Vista sleep problem where PC won't go to sleep. Thanks Microsoft