My two cents:
I have bought 3 new machines (2 lathes & a mill) in the last 12 months. In all 3 cases, I bought new Precision Matthews machines. So far, I have had zero problems. In fact, it has gone very smoothly, although I should mention that I ended up flattening the family finances.
I am sure that previously owned machines can deliver tremendous value, but the machine school that I go to uses (and sells) used machines, and I have seen a lot of slop (!) and issues that would not arise on a new machine. Working on these large but tired machines is usually great, but many are missing levers (and functions). Working on such worn machines may not provide as good of an operator experience as working on a machine that is new (even if that machine came from China or Taiwan).