My Mother had a Necchi. It was a wonderful machine. It came in a nice wooden cabinet. She bought a Fleetwood for me when I graduated from high school. She thought it was a Necchi as they were sold at the same store. I was told my Fleetwood was a cheap knockoff. My Fleetwood was given to me in 1967. In 1998 after sitting without use over 25 years it would not sew. About 2005 I tried again, nothing. I oiled it.... Next day it sewed beautifully. I sent it to a quilt guild in Cedar Rapids, Iowa after they were flooded out and lost all quilting tools & machines. We bought a Janome 6600P for me.
I would say they will both be great machines if you oil & clean them. They will not probably be collector's items.