What do you think of synthetic marajuana?

in Australia we can buy synthetic weed that is legal can cannot be tested in a drug test. How ironic? It has the same effect of weed in general, minus most of the bad effects like paranoia, the marajuhana hangover, plus a company makes it so you know that you're getting what you pay for everytime. What do you guys think of this and the fact that weed is still illegal here despite this product being almost exactly the same.