I own a Powerstar 75, love it. But the main issues with New hollands are the cables. I stole mine for 27K (4wd, cab, loader, 1500hrs) so replacing cables every so often isn't a huge issue to me.
I do not know but i would find out what platform the TN series came from, if it's a powerstar type tractor, id go all for it, would not hesitate but the workmasters have some major issues. I would avoid a workmaster, and yes New Holland is a blue case. I don't know how far back they go with that but essentially the Workmaster series is the farmall series A and the powerstar is the farmall series C
I live in waco....therefore, I am ready to move elsewhere.