Liquidity is awfull on globex but as for price structure I don't agree it acts as the spot that is to say without the usual spread between the spot and the future contract. When RTH opens spread is restablished again. This is very funny to observe and I will illustrate that later with pictures for last friday's session for example.
Quote from vulture:
The only other times that I have seen GLobex trade with a similar price structure, similar liquidity to RTH is during either A) Global financial crisis or B) Earnings season (typically mid January, mid April, mid July, mid October)