Opportunity is missed by most people because it is dressed in overalls and looks like work. - Thomas Edison
I'd say it's superior to SF by a good margin.
Union cotton white prints as easy as any other color ink manually. It was my only white for many years. With all the 50/50 blends now I use legacy LB. I only like having one white. The cotton white manually is a dream. It is not sticky and you don't have to modify it ever. Out of all the inks that one has a nice smell, like I'm the only one smelling inks.
(But I was a little shocked when I went to open what was supposed to have been Black!)