I have not experienced this with the 62. It may be due to the forced power cycle it does on its own when you disconnect the USB cable. On my old 60, there was a setting for "External power loss" to leave the GPS on or off when that happens. On the 62, this option seems to be missing, so no matter what I do, when I disconnect the cable from the unit, it powers off. After power on, everything works fine as usual.
I do find the latest firmware release to be slower than the previous, making an already slow unit that much more painful to use. I hope that the issues with car units will not slow Garmin's progress down in fixing all the bugs in the 62, or I'll end up selling it off due to impatience.