spot welder

I'm itching to buy something and have been looking at the eastwood cataloge.
They offer a spot weld gun that attaches to your stick welder leads, this
one has small weld sticks for making the arc.  Has anyone used one of these?
Did it work ok?  I have a 90amp GMAW rig, I'd planned to use and will use.
But this may be a handy tool as well, I'd use it with my lincoln arc setup.

Thanks,

Charlie
1959 Sprite aka Trailer Maiden