theres drug use, then theres drug abuse.
As you said everyone is different but I get decent visuals from 25 - 50mg's, something must be up with your aMT if you need 150mg's
As I've said, there's nothing wrong with the aMT, other people have taken the same stuff at much lower doses (25-80mg) and tripped. However due to the extreme amounts I have taken in the past it does not make me trip at lower doses any more. First few times I did it I did a sensible amount and tripped just fine. Still use the same supplier too.