Is it wise to trust the system as far as accepting and installing updates that appear in the Update Manager? After I updated to kernel 3.4 it now reports about 850 updates at about 400mb, which would take all day on a usb tethered connection.
The answer is Yes as long as you can trust the sources. It is perfectly Okay to download and install the updates that appear in the update manager if you use only the standard Ubuntu software sources.
But, if you added PPAs to your software source list, You will receive updates from those PPAs too. So, in that situation your trust level depends on the trust you have on those PPAs. Though you can update your system with PPAs enabled, I strongly recommend to disable PPAs before doing updates. This will help you to have much error free system, because installing updates from PPAs can arise many issues in future.
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