So you mean which in YOUR opinion are NOT (Milestones or Psy?)
For not psytrance
Love Juno Reactor albums and most are classed as Psy-Trance but I don't really think Transmissions or Labyrinth are.
But then it is hard to define Psy as I find both albums very psychedelic but not so fitting in with the goa/psy image.
for not milestones though
Before I mentioned Hallucinogen - The Lone Deranger, considered by many to be a milestone in Psy just like his first release Twisted. Although I find twisted groundbreaking I just don't get what was so fresh & amazing about TLD. People hark on about it like it was the second coming but I found it very average, not nearly as psychedelic as twisted and I have to say too cheesy.