So you think it's worth using the non-default driver.
I think it's worth using whatever driver works :)
That means that I
must switch off auto-updates, after reinstalling the non-default driver,
No, it doesn't as I understand it. They have provided a manual
solution to "fix" the driver as and when it breaks after a system
update, and the updates wont install (usually) until you confirm them
to in update-manager, or manually update them yourself.
and before going back online, and that I must install DKMS before
switching auto-updates back on,
I'm not sure if DKMS would resolve this, it is worth having a look at
the documentation for it though.