If the tools hold up, a barfed subspindle/live tooled lathe can run unmanned for a long time, and the job could be setup with minimal investment, just the soft jaws.
Now you could go out and buy 2 Haas SL-20s and a VF-2 with a 4th for less than the Mori live tooled subspindle lathe and have very close to 3 times the production, with more capabilities. I guess it boils down to paying for labor vs. paying for the machine.
I am not sure I agree with the first comment above about "minimal investment"; the machine the soft jaws bolt into is not cheap.
The other two quotes more or less describe my conclusions. You always have to pay at least some labor costs so that can be a wash. If you are guaranteed you will never have to run simple parts the fancy multi-spindle machine may be the one to have, but if you do a mix of parts you may be better off having two or three less complicated machines for the same initial cost.