I've done some work on them down here, (Mechanical) I'd rate them highly. There aren't many of them down here (Aust), but I expect that would be pro rata in the States. There more known for production lines in Auto Motive. I've seen those at Ford down here in Geelong at the engine plant. I was in the plant during the same time that line went in.
There are a few stand alone vertical CNC's, I've worked on. I'd rate them among to top hand full of Japanese builders.
In my own work shop, I have a mechanical Enshu Vertical mill, from the 60's. They had casting down by then, its built like a brick shit house.
Regards Phil.