On Feb 27, 1:13*pm, fred wrote:
Never had or used one, or even knew of their existence until recently
but now have to install 100-200 of them.

The usual problem with rivet guns is grip at the jaws. This isn't a
problem with threaded inserts, as you're gripping with the thread. If
you're putting in Clinch nuts (which are useful up to about M5) or
compressible tube threaded rivets in sizes up to M6, then a cheap
setting tool is fine. If you're trying to collapse the tube for ones
from M8 and upwards, then you're dealing with an appreciable force and
a two-handled setter is useful, to avoid wear on both you and the
tool.

For M12, you want a hydraulic tool.