I don't know the difference between the 986 and the 989, but I have had a 
989 for over fifteen years.  It tunes everything imaginable, and some things 
unimaginable.  It has two coax antenna, a dummy load, and a longwire and 
ballenced output options.  I do take the top off once a year to clean the 
wheel assembly for the roller inductor.  You can knock the roller off the 
end of the coil, but that is an easy fix.  If you are cranking the roller to 
fast, that can happen.
I would look for a used one I think, they are around.